diff options
Diffstat (limited to 'security/smack/smack_lsm.c')
| -rw-r--r-- | security/smack/smack_lsm.c | 2637 |
1 files changed, 2056 insertions, 581 deletions
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index 732ba27923c..f2c30801ce4 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3,10 +3,15 @@ * * This file contains the smack hook function implementations. * - * Author: + * Authors: * Casey Schaufler <casey@schaufler-ca.com> + * Jarkko Sakkinen <jarkko.sakkinen@intel.com> * * Copyright (C) 2007 Casey Schaufler <casey@schaufler-ca.com> + * Copyright (C) 2009 Hewlett-Packard Development Company, L.P. + * Paul Moore <paul@paul-moore.com> + * Copyright (C) 2010 Nokia Corporation + * Copyright (C) 2011 Intel Corporation. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2, @@ -17,24 +22,37 @@ #include <linux/pagemap.h> #include <linux/mount.h> #include <linux/stat.h> -#include <linux/ext2_fs.h> #include <linux/kd.h> #include <asm/ioctls.h> +#include <linux/ip.h> #include <linux/tcp.h> #include <linux/udp.h> +#include <linux/dccp.h> +#include <linux/slab.h> #include <linux/mutex.h> #include <linux/pipe_fs_i.h> -#include <net/netlabel.h> #include <net/cipso_ipv4.h> - +#include <net/ip.h> +#include <net/ipv6.h> +#include <linux/audit.h> +#include <linux/magic.h> +#include <linux/dcache.h> +#include <linux/personality.h> +#include <linux/msg.h> +#include <linux/shm.h> +#include <linux/binfmts.h> #include "smack.h" -/* - * I hope these are the hokeyist lines of code in the module. Casey. - */ -#define DEVPTS_SUPER_MAGIC 0x1cd1 -#define SOCKFS_MAGIC 0x534F434B -#define TMPFS_MAGIC 0x01021994 +#define task_security(task) (task_cred_xxx((task), security)) + +#define TRANS_TRUE "TRUE" +#define TRANS_TRUE_SIZE 4 + +#define SMK_CONNECTING 0 +#define SMK_RECEIVING 1 +#define SMK_SENDING 2 + +LIST_HEAD(smk_ipv6_port_list); /** * smk_fetch - Fetch the smack label from a file. @@ -44,19 +62,27 @@ * Returns a pointer to the master list entry for the Smack label * or NULL if there was no label to fetch. */ -static char *smk_fetch(struct inode *ip, struct dentry *dp) +static struct smack_known *smk_fetch(const char *name, struct inode *ip, + struct dentry *dp) { int rc; - char in[SMK_LABELLEN]; + char *buffer; + struct smack_known *skp = NULL; if (ip->i_op->getxattr == NULL) return NULL; - rc = ip->i_op->getxattr(dp, XATTR_NAME_SMACK, in, SMK_LABELLEN); - if (rc < 0) + buffer = kzalloc(SMK_LONGLABEL, GFP_KERNEL); + if (buffer == NULL) return NULL; - return smk_import(in, rc); + rc = ip->i_op->getxattr(dp, name, buffer, SMK_LONGLABEL); + if (rc > 0) + skp = smk_import_entry(buffer, rc); + + kfree(buffer); + + return skp; } /** @@ -69,7 +95,7 @@ struct inode_smack *new_inode_smack(char *smack) { struct inode_smack *isp; - isp = kzalloc(sizeof(struct inode_smack), GFP_KERNEL); + isp = kzalloc(sizeof(struct inode_smack), GFP_NOFS); if (isp == NULL) return NULL; @@ -80,56 +106,193 @@ struct inode_smack *new_inode_smack(char *smack) return isp; } +/** + * new_task_smack - allocate a task security blob + * @smack: a pointer to the Smack label to use in the blob + * + * Returns the new blob or NULL if there's no memory available + */ +static struct task_smack *new_task_smack(struct smack_known *task, + struct smack_known *forked, gfp_t gfp) +{ + struct task_smack *tsp; + + tsp = kzalloc(sizeof(struct task_smack), gfp); + if (tsp == NULL) + return NULL; + + tsp->smk_task = task; + tsp->smk_forked = forked; + INIT_LIST_HEAD(&tsp->smk_rules); + mutex_init(&tsp->smk_rules_lock); + + return tsp; +} + +/** + * smk_copy_rules - copy a rule set + * @nhead - new rules header pointer + * @ohead - old rules header pointer + * + * Returns 0 on success, -ENOMEM on error + */ +static int smk_copy_rules(struct list_head *nhead, struct list_head *ohead, + gfp_t gfp) +{ + struct smack_rule *nrp; + struct smack_rule *orp; + int rc = 0; + + INIT_LIST_HEAD(nhead); + + list_for_each_entry_rcu(orp, ohead, list) { + nrp = kzalloc(sizeof(struct smack_rule), gfp); + if (nrp == NULL) { + rc = -ENOMEM; + break; + } + *nrp = *orp; + list_add_rcu(&nrp->list, nhead); + } + return rc; +} + +/** + * smk_ptrace_mode - helper function for converting PTRACE_MODE_* into MAY_* + * @mode - input mode in form of PTRACE_MODE_* + * + * Returns a converted MAY_* mode usable by smack rules + */ +static inline unsigned int smk_ptrace_mode(unsigned int mode) +{ + switch (mode) { + case PTRACE_MODE_READ: + return MAY_READ; + case PTRACE_MODE_ATTACH: + return MAY_READWRITE; + } + + return 0; +} + +/** + * smk_ptrace_rule_check - helper for ptrace access + * @tracer: tracer process + * @tracee_label: label of the process that's about to be traced, + * the pointer must originate from smack structures + * @mode: ptrace attachment mode (PTRACE_MODE_*) + * @func: name of the function that called us, used for audit + * + * Returns 0 on access granted, -error on error + */ +static int smk_ptrace_rule_check(struct task_struct *tracer, char *tracee_label, + unsigned int mode, const char *func) +{ + int rc; + struct smk_audit_info ad, *saip = NULL; + struct task_smack *tsp; + struct smack_known *skp; + + if ((mode & PTRACE_MODE_NOAUDIT) == 0) { + smk_ad_init(&ad, func, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, tracer); + saip = &ad; + } + + tsp = task_security(tracer); + skp = smk_of_task(tsp); + + if ((mode & PTRACE_MODE_ATTACH) && + (smack_ptrace_rule == SMACK_PTRACE_EXACT || + smack_ptrace_rule == SMACK_PTRACE_DRACONIAN)) { + if (skp->smk_known == tracee_label) + rc = 0; + else if (smack_ptrace_rule == SMACK_PTRACE_DRACONIAN) + rc = -EACCES; + else if (capable(CAP_SYS_PTRACE)) + rc = 0; + else + rc = -EACCES; + + if (saip) + smack_log(skp->smk_known, tracee_label, 0, rc, saip); + + return rc; + } + + /* In case of rule==SMACK_PTRACE_DEFAULT or mode==PTRACE_MODE_READ */ + rc = smk_tskacc(tsp, tracee_label, smk_ptrace_mode(mode), saip); + return rc; +} + /* * LSM hooks. * We he, that is fun! */ /** - * smack_ptrace - Smack approval on ptrace - * @ptp: parent task pointer + * smack_ptrace_access_check - Smack approval on PTRACE_ATTACH * @ctp: child task pointer + * @mode: ptrace attachment mode (PTRACE_MODE_*) * * Returns 0 if access is OK, an error code otherwise * - * Do the capability checks, and require read and write. + * Do the capability checks. */ -static int smack_ptrace(struct task_struct *ptp, struct task_struct *ctp) +static int smack_ptrace_access_check(struct task_struct *ctp, unsigned int mode) { int rc; + struct smack_known *skp; - rc = cap_ptrace(ptp, ctp); + rc = cap_ptrace_access_check(ctp, mode); if (rc != 0) return rc; - rc = smk_access(ptp->security, ctp->security, MAY_READWRITE); - if (rc != 0 && __capable(ptp, CAP_MAC_OVERRIDE)) - return 0; + skp = smk_of_task(task_security(ctp)); + rc = smk_ptrace_rule_check(current, skp->smk_known, mode, __func__); return rc; } /** - * smack_syslog - Smack approval on syslog - * @type: message type + * smack_ptrace_traceme - Smack approval on PTRACE_TRACEME + * @ptp: parent task pointer * - * Require that the task has the floor label + * Returns 0 if access is OK, an error code otherwise * - * Returns 0 on success, error code otherwise. + * Do the capability checks, and require PTRACE_MODE_ATTACH. */ -static int smack_syslog(int type) +static int smack_ptrace_traceme(struct task_struct *ptp) { int rc; - char *sp = current->security; + struct smack_known *skp; - rc = cap_syslog(type); + rc = cap_ptrace_traceme(ptp); if (rc != 0) return rc; - if (capable(CAP_MAC_OVERRIDE)) + skp = smk_of_task(current_security()); + + rc = smk_ptrace_rule_check(ptp, skp->smk_known, + PTRACE_MODE_ATTACH, __func__); + return rc; +} + +/** + * smack_syslog - Smack approval on syslog + * @type: message type + * + * Returns 0 on success, error code otherwise. + */ +static int smack_syslog(int typefrom_file) +{ + int rc = 0; + struct smack_known *skp = smk_of_current(); + + if (smack_privileged(CAP_MAC_OVERRIDE)) return 0; - if (sp != smack_known_floor.smk_known) + if (smack_syslog_label != NULL && smack_syslog_label != skp) rc = -EACCES; return rc; @@ -159,9 +322,9 @@ static int smack_sb_alloc_security(struct super_block *sb) sbsp->smk_default = smack_known_floor.smk_known; sbsp->smk_floor = smack_known_floor.smk_known; sbsp->smk_hat = smack_known_hat.smk_known; - sbsp->smk_initialized = 0; - spin_lock_init(&sbsp->smk_sblock); - + /* + * smk_initialized will be zero from kzalloc. + */ sb->s_security = sbsp; return 0; @@ -180,9 +343,8 @@ static void smack_sb_free_security(struct super_block *sb) /** * smack_sb_copy_data - copy mount options data for processing - * @type: file system type * @orig: where to start - * @smackopts + * @smackopts: mount options string * * Returns 0 on success or -ENOMEM on error. * @@ -206,6 +368,8 @@ static int smack_sb_copy_data(char *orig, char *smackopts) dp = smackopts; else if (strstr(cp, SMK_FSROOT) == cp) dp = smackopts; + else if (strstr(cp, SMK_FSTRANS) == cp) + dp = smackopts; else dp = otheropts; @@ -227,27 +391,28 @@ static int smack_sb_copy_data(char *orig, char *smackopts) /** * smack_sb_kern_mount - Smack specific mount processing * @sb: the file system superblock + * @flags: the mount flags * @data: the smack mount options * * Returns 0 on success, an error code on failure */ -static int smack_sb_kern_mount(struct super_block *sb, void *data) +static int smack_sb_kern_mount(struct super_block *sb, int flags, void *data) { struct dentry *root = sb->s_root; struct inode *inode = root->d_inode; struct superblock_smack *sp = sb->s_security; struct inode_smack *isp; + struct smack_known *skp; char *op; char *commap; char *nsp; + int transmute = 0; + int specified = 0; - spin_lock(&sp->smk_sblock); - if (sp->smk_initialized != 0) { - spin_unlock(&sp->smk_sblock); + if (sp->smk_initialized) return 0; - } + sp->smk_initialized = 1; - spin_unlock(&sp->smk_sblock); for (op = data; op != NULL; op = commap) { commap = strchr(op, ','); @@ -257,36 +422,71 @@ static int smack_sb_kern_mount(struct super_block *sb, void *data) if (strncmp(op, SMK_FSHAT, strlen(SMK_FSHAT)) == 0) { op += strlen(SMK_FSHAT); nsp = smk_import(op, 0); - if (nsp != NULL) + if (nsp != NULL) { sp->smk_hat = nsp; + specified = 1; + } } else if (strncmp(op, SMK_FSFLOOR, strlen(SMK_FSFLOOR)) == 0) { op += strlen(SMK_FSFLOOR); nsp = smk_import(op, 0); - if (nsp != NULL) + if (nsp != NULL) { sp->smk_floor = nsp; + specified = 1; + } } else if (strncmp(op, SMK_FSDEFAULT, strlen(SMK_FSDEFAULT)) == 0) { op += strlen(SMK_FSDEFAULT); nsp = smk_import(op, 0); - if (nsp != NULL) + if (nsp != NULL) { sp->smk_default = nsp; + specified = 1; + } } else if (strncmp(op, SMK_FSROOT, strlen(SMK_FSROOT)) == 0) { op += strlen(SMK_FSROOT); nsp = smk_import(op, 0); - if (nsp != NULL) + if (nsp != NULL) { sp->smk_root = nsp; + specified = 1; + } + } else if (strncmp(op, SMK_FSTRANS, strlen(SMK_FSTRANS)) == 0) { + op += strlen(SMK_FSTRANS); + nsp = smk_import(op, 0); + if (nsp != NULL) { + sp->smk_root = nsp; + transmute = 1; + specified = 1; + } } } + if (!smack_privileged(CAP_MAC_ADMIN)) { + /* + * Unprivileged mounts don't get to specify Smack values. + */ + if (specified) + return -EPERM; + /* + * Unprivileged mounts get root and default from the caller. + */ + skp = smk_of_current(); + sp->smk_root = skp->smk_known; + sp->smk_default = skp->smk_known; + } /* * Initialize the root inode. */ isp = inode->i_security; - if (isp == NULL) - inode->i_security = new_inode_smack(sp->smk_root); - else + if (isp == NULL) { + isp = new_inode_smack(sp->smk_root); + if (isp == NULL) + return -ENOMEM; + inode->i_security = isp; + } else isp->smk_inode = sp->smk_root; + if (transmute) + isp->smk_flags |= SMK_INODE_TRANSMUTE; + return 0; } @@ -300,44 +500,97 @@ static int smack_sb_kern_mount(struct super_block *sb, void *data) static int smack_sb_statfs(struct dentry *dentry) { struct superblock_smack *sbp = dentry->d_sb->s_security; + int rc; + struct smk_audit_info ad; - return smk_curacc(sbp->smk_floor, MAY_READ); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + + rc = smk_curacc(sbp->smk_floor, MAY_READ, &ad); + return rc; } +/* + * BPRM hooks + */ + /** - * smack_sb_mount - Smack check for mounting - * @dev_name: unused - * @nd: mount point - * @type: unused - * @flags: unused - * @data: unused + * smack_bprm_set_creds - set creds for exec + * @bprm: the exec information + * + * Returns 0 if it gets a blob, -EPERM if exec forbidden and -ENOMEM otherwise + */ +static int smack_bprm_set_creds(struct linux_binprm *bprm) +{ + struct inode *inode = file_inode(bprm->file); + struct task_smack *bsp = bprm->cred->security; + struct inode_smack *isp; + int rc; + + rc = cap_bprm_set_creds(bprm); + if (rc != 0) + return rc; + + if (bprm->cred_prepared) + return 0; + + isp = inode->i_security; + if (isp->smk_task == NULL || isp->smk_task == bsp->smk_task) + return 0; + + if (bprm->unsafe & (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) { + struct task_struct *tracer; + rc = 0; + + rcu_read_lock(); + tracer = ptrace_parent(current); + if (likely(tracer != NULL)) + rc = smk_ptrace_rule_check(tracer, + isp->smk_task->smk_known, + PTRACE_MODE_ATTACH, + __func__); + rcu_read_unlock(); + + if (rc != 0) + return rc; + } else if (bprm->unsafe) + return -EPERM; + + bsp->smk_task = isp->smk_task; + bprm->per_clear |= PER_CLEAR_ON_SETID; + + return 0; +} + +/** + * smack_bprm_committing_creds - Prepare to install the new credentials + * from bprm. * - * Returns 0 if current can write the floor of the filesystem - * being mounted on, an error code otherwise. + * @bprm: binprm for exec */ -static int smack_sb_mount(char *dev_name, struct nameidata *nd, - char *type, unsigned long flags, void *data) +static void smack_bprm_committing_creds(struct linux_binprm *bprm) { - struct superblock_smack *sbp = nd->path.mnt->mnt_sb->s_security; + struct task_smack *bsp = bprm->cred->security; - return smk_curacc(sbp->smk_floor, MAY_WRITE); + if (bsp->smk_task != bsp->smk_forked) + current->pdeath_signal = 0; } /** - * smack_sb_umount - Smack check for unmounting - * @mnt: file system to unmount - * @flags: unused + * smack_bprm_secureexec - Return the decision to use secureexec. + * @bprm: binprm for exec * - * Returns 0 if current can write the floor of the filesystem - * being unmounted, an error code otherwise. + * Returns 0 on success. */ -static int smack_sb_umount(struct vfsmount *mnt, int flags) +static int smack_bprm_secureexec(struct linux_binprm *bprm) { - struct superblock_smack *sbp; + struct task_smack *tsp = current_security(); + int ret = cap_bprm_secureexec(bprm); - sbp = mnt->mnt_sb->s_security; + if (!ret && (tsp->smk_task != tsp->smk_forked)) + ret = 1; - return smk_curacc(sbp->smk_floor, MAY_WRITE); + return ret; } /* @@ -346,13 +599,15 @@ static int smack_sb_umount(struct vfsmount *mnt, int flags) /** * smack_inode_alloc_security - allocate an inode blob - * @inode - the inode in need of a blob + * @inode: the inode in need of a blob * * Returns 0 if it gets a blob, -ENOMEM otherwise */ static int smack_inode_alloc_security(struct inode *inode) { - inode->i_security = new_inode_smack(current->security); + struct smack_known *skp = smk_of_current(); + + inode->i_security = new_inode_smack(skp->smk_known); if (inode->i_security == NULL) return -ENOMEM; return 0; @@ -360,7 +615,7 @@ static int smack_inode_alloc_security(struct inode *inode) /** * smack_inode_free_security - free an inode blob - * @inode - the inode with a blob + * @inode: the inode with a blob * * Clears the blob pointer in inode */ @@ -374,6 +629,7 @@ static void smack_inode_free_security(struct inode *inode) * smack_inode_init_security - copy out the smack from an inode * @inode: the inode * @dir: unused + * @qstr: unused * @name: where to put the attribute name * @value: where to put the attribute value * @len: where to put the length of the attribute @@ -381,18 +637,36 @@ static void smack_inode_free_security(struct inode *inode) * Returns 0 if it all works out, -ENOMEM if there's no memory */ static int smack_inode_init_security(struct inode *inode, struct inode *dir, - char **name, void **value, size_t *len) + const struct qstr *qstr, const char **name, + void **value, size_t *len) { + struct inode_smack *issp = inode->i_security; + struct smack_known *skp = smk_of_current(); char *isp = smk_of_inode(inode); + char *dsp = smk_of_inode(dir); + int may; - if (name) { - *name = kstrdup(XATTR_SMACK_SUFFIX, GFP_KERNEL); - if (*name == NULL) - return -ENOMEM; - } + if (name) + *name = XATTR_SMACK_SUFFIX; if (value) { - *value = kstrdup(isp, GFP_KERNEL); + rcu_read_lock(); + may = smk_access_entry(skp->smk_known, dsp, &skp->smk_rules); + rcu_read_unlock(); + + /* + * If the access rule allows transmutation and + * the directory requests transmutation then + * by all means transmute. + * Mark the inode as changed. + */ + if (may > 0 && ((may & MAY_TRANSMUTE) != 0) && + smk_inode_transmutable(dir)) { + isp = dsp; + issp->smk_flags |= SMK_INODE_CHANGED; + } + + *value = kstrdup(isp, GFP_NOFS); if (*value == NULL) return -ENOMEM; } @@ -414,15 +688,20 @@ static int smack_inode_init_security(struct inode *inode, struct inode *dir, static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry) { - int rc; char *isp; + struct smk_audit_info ad; + int rc; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); - rc = smk_curacc(isp, MAY_WRITE); + rc = smk_curacc(isp, MAY_WRITE, &ad); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); - rc = smk_curacc(isp, MAY_WRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); + rc = smk_curacc(isp, MAY_WRITE, &ad); } return rc; @@ -439,18 +718,24 @@ static int smack_inode_link(struct dentry *old_dentry, struct inode *dir, static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) { struct inode *ip = dentry->d_inode; + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + /* * You need write access to the thing you're unlinking */ - rc = smk_curacc(smk_of_inode(ip), MAY_WRITE); - if (rc == 0) + rc = smk_curacc(smk_of_inode(ip), MAY_WRITE, &ad); + if (rc == 0) { /* * You also need write access to the containing directory */ - rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); - + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); + smk_ad_setfield_u_fs_inode(&ad, dir); + rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); + } return rc; } @@ -464,17 +749,24 @@ static int smack_inode_unlink(struct inode *dir, struct dentry *dentry) */ static int smack_inode_rmdir(struct inode *dir, struct dentry *dentry) { + struct smk_audit_info ad; int rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + /* * You need write access to the thing you're removing */ - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); - if (rc == 0) + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); + if (rc == 0) { /* * You also need write access to the containing directory */ - rc = smk_curacc(smk_of_inode(dir), MAY_WRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); + smk_ad_setfield_u_fs_inode(&ad, dir); + rc = smk_curacc(smk_of_inode(dir), MAY_WRITE, &ad); + } return rc; } @@ -498,15 +790,19 @@ static int smack_inode_rename(struct inode *old_inode, { int rc; char *isp; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, old_dentry); isp = smk_of_inode(old_dentry->d_inode); - rc = smk_curacc(isp, MAY_READWRITE); + rc = smk_curacc(isp, MAY_READWRITE, &ad); if (rc == 0 && new_dentry->d_inode != NULL) { isp = smk_of_inode(new_dentry->d_inode); - rc = smk_curacc(isp, MAY_READWRITE); + smk_ad_setfield_u_fs_path_dentry(&ad, new_dentry); + rc = smk_curacc(isp, MAY_READWRITE, &ad); } - return rc; } @@ -514,22 +810,29 @@ static int smack_inode_rename(struct inode *old_inode, * smack_inode_permission - Smack version of permission() * @inode: the inode in question * @mask: the access requested - * @nd: unused * * This is the important Smack hook. * * Returns 0 if access is permitted, -EACCES otherwise */ -static int smack_inode_permission(struct inode *inode, int mask, - struct nameidata *nd) +static int smack_inode_permission(struct inode *inode, int mask) { + struct smk_audit_info ad; + int no_block = mask & MAY_NOT_BLOCK; + + mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND); /* * No permission to check. Existence test. Yup, it's there. */ if (mask == 0) return 0; - return smk_curacc(smk_of_inode(inode), mask); + /* May be droppable after audit */ + if (no_block) + return -ECHILD; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_INODE); + smk_ad_setfield_u_fs_inode(&ad, inode); + return smk_curacc(smk_of_inode(inode), mask, &ad); } /** @@ -541,13 +844,16 @@ static int smack_inode_permission(struct inode *inode, int mask, */ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) { + struct smk_audit_info ad; /* * Need to allow for clearing the setuid bit. */ if (iattr->ia_valid & ATTR_FORCE) return 0; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); } /** @@ -559,7 +865,15 @@ static int smack_inode_setattr(struct dentry *dentry, struct iattr *iattr) */ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) { - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); + struct smk_audit_info ad; + struct path path; + + path.dentry = dentry; + path.mnt = mnt; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, path); + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); } /** @@ -574,21 +888,52 @@ static int smack_inode_getattr(struct vfsmount *mnt, struct dentry *dentry) * * Returns 0 if access is permitted, an error code otherwise */ -static int smack_inode_setxattr(struct dentry *dentry, char *name, - void *value, size_t size, int flags) +static int smack_inode_setxattr(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags) { + struct smk_audit_info ad; + struct smack_known *skp; + int check_priv = 0; + int check_import = 0; + int check_star = 0; int rc = 0; + /* + * Check label validity here so import won't fail in post_setxattr + */ if (strcmp(name, XATTR_NAME_SMACK) == 0 || strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { - if (!capable(CAP_MAC_ADMIN)) - rc = -EPERM; + check_priv = 1; + check_import = 1; + } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || + strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { + check_priv = 1; + check_import = 1; + check_star = 1; + } else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { + check_priv = 1; + if (size != TRANS_TRUE_SIZE || + strncmp(value, TRANS_TRUE, TRANS_TRUE_SIZE) != 0) + rc = -EINVAL; } else rc = cap_inode_setxattr(dentry, name, value, size, flags); + if (check_priv && !smack_privileged(CAP_MAC_ADMIN)) + rc = -EPERM; + + if (rc == 0 && check_import) { + skp = smk_import_entry(value, size); + if (skp == NULL || (check_star && + (skp == &smack_known_star || skp == &smack_known_web))) + rc = -EINVAL; + } + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + if (rc == 0) - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); return rc; } @@ -604,49 +949,58 @@ static int smack_inode_setxattr(struct dentry *dentry, char *name, * Set the pointer in the inode blob to the entry found * in the master label list. */ -static void smack_inode_post_setxattr(struct dentry *dentry, char *name, - void *value, size_t size, int flags) +static void smack_inode_post_setxattr(struct dentry *dentry, const char *name, + const void *value, size_t size, int flags) { - struct inode_smack *isp; - char *nsp; - - /* - * Not SMACK - */ - if (strcmp(name, XATTR_NAME_SMACK)) - return; + struct smack_known *skp; + struct inode_smack *isp = dentry->d_inode->i_security; - if (size >= SMK_LABELLEN) + if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) { + isp->smk_flags |= SMK_INODE_TRANSMUTE; return; + } - isp = dentry->d_inode->i_security; - - /* - * No locking is done here. This is a pointer - * assignment. - */ - nsp = smk_import(value, size); - if (nsp != NULL) - isp->smk_inode = nsp; - else - isp->smk_inode = smack_known_invalid.smk_known; + if (strcmp(name, XATTR_NAME_SMACK) == 0) { + skp = smk_import_entry(value, size); + if (skp != NULL) + isp->smk_inode = skp->smk_known; + else + isp->smk_inode = smack_known_invalid.smk_known; + } else if (strcmp(name, XATTR_NAME_SMACKEXEC) == 0) { + skp = smk_import_entry(value, size); + if (skp != NULL) + isp->smk_task = skp; + else + isp->smk_task = &smack_known_invalid; + } else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { + skp = smk_import_entry(value, size); + if (skp != NULL) + isp->smk_mmap = skp; + else + isp->smk_mmap = &smack_known_invalid; + } return; } -/* +/** * smack_inode_getxattr - Smack check on getxattr * @dentry: the object * @name: unused * * Returns 0 if access is permitted, an error code otherwise */ -static int smack_inode_getxattr(struct dentry *dentry, char *name) +static int smack_inode_getxattr(struct dentry *dentry, const char *name) { - return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + + return smk_curacc(smk_of_inode(dentry->d_inode), MAY_READ, &ad); } -/* +/** * smack_inode_removexattr - Smack check on removexattr * @dentry: the object * @name: name of the attribute @@ -655,22 +1009,48 @@ static int smack_inode_getxattr(struct dentry *dentry, char *name) * * Returns 0 if access is permitted, an error code otherwise */ -static int smack_inode_removexattr(struct dentry *dentry, char *name) +static int smack_inode_removexattr(struct dentry *dentry, const char *name) { + struct inode_smack *isp; + struct smk_audit_info ad; int rc = 0; if (strcmp(name, XATTR_NAME_SMACK) == 0 || strcmp(name, XATTR_NAME_SMACKIPIN) == 0 || - strcmp(name, XATTR_NAME_SMACKIPOUT) == 0) { - if (!capable(CAP_MAC_ADMIN)) + strcmp(name, XATTR_NAME_SMACKIPOUT) == 0 || + strcmp(name, XATTR_NAME_SMACKEXEC) == 0 || + strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0 || + strcmp(name, XATTR_NAME_SMACKMMAP) == 0) { + if (!smack_privileged(CAP_MAC_ADMIN)) rc = -EPERM; } else rc = cap_inode_removexattr(dentry, name); - if (rc == 0) - rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE); + if (rc != 0) + return rc; - return rc; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_DENTRY); + smk_ad_setfield_u_fs_path_dentry(&ad, dentry); + + rc = smk_curacc(smk_of_inode(dentry->d_inode), MAY_WRITE, &ad); + if (rc != 0) + return rc; + + isp = dentry->d_inode->i_security; + /* + * Don't do anything special for these. + * XATTR_NAME_SMACKIPIN + * XATTR_NAME_SMACKIPOUT + * XATTR_NAME_SMACKEXEC + */ + if (strcmp(name, XATTR_NAME_SMACK) == 0) + isp->smk_task = NULL; + else if (strcmp(name, XATTR_NAME_SMACKMMAP) == 0) + isp->smk_mmap = NULL; + else if (strcmp(name, XATTR_NAME_SMACKTRANSMUTE) == 0) + isp->smk_flags &= ~SMK_INODE_TRANSMUTE; + + return 0; } /** @@ -678,8 +1058,7 @@ static int smack_inode_removexattr(struct dentry *dentry, char *name) * @inode: the object * @name: attribute name * @buffer: where to put the result - * @size: size of the buffer - * @err: unused + * @alloc: unused * * Returns the size of the attribute or an error code */ @@ -716,9 +1095,9 @@ static int smack_inode_getsecurity(const struct inode *inode, ssp = sock->sk->sk_security; if (strcmp(name, XATTR_SMACK_IPIN) == 0) - isp = ssp->smk_in; + isp = ssp->smk_in->smk_known; else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) - isp = ssp->smk_out; + isp = ssp->smk_out->smk_known; else return -EOPNOTSUPP; @@ -752,6 +1131,18 @@ static int smack_inode_listsecurity(struct inode *inode, char *buffer, return -EINVAL; } +/** + * smack_inode_getsecid - Extract inode's security id + * @inode: inode to extract the info from + * @secid: where result will be saved + */ +static void smack_inode_getsecid(const struct inode *inode, u32 *secid) +{ + struct inode_smack *isp = inode->i_security; + + *secid = smack_to_secid(isp->smk_inode); +} + /* * File Hooks */ @@ -786,7 +1177,9 @@ static int smack_file_permission(struct file *file, int mask) */ static int smack_file_alloc_security(struct file *file) { - file->f_security = current->security; + struct smack_known *skp = smk_of_current(); + + file->f_security = skp->smk_known; return 0; } @@ -816,12 +1209,16 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { int rc = 0; + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); if (_IOC_DIR(cmd) & _IOC_WRITE) - rc = smk_curacc(file->f_security, MAY_WRITE); + rc = smk_curacc(file->f_security, MAY_WRITE, &ad); if (rc == 0 && (_IOC_DIR(cmd) & _IOC_READ)) - rc = smk_curacc(file->f_security, MAY_READ); + rc = smk_curacc(file->f_security, MAY_READ, &ad); return rc; } @@ -829,13 +1226,17 @@ static int smack_file_ioctl(struct file *file, unsigned int cmd, /** * smack_file_lock - Smack check on file locking * @file: the object - * @cmd unused + * @cmd: unused * - * Returns 0 if current has write access, error code otherwise + * Returns 0 if current has lock access, error code otherwise */ static int smack_file_lock(struct file *file, unsigned int cmd) { - return smk_curacc(file->f_security, MAY_WRITE); + struct smk_audit_info ad; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + return smk_curacc(file->f_security, MAY_LOCK, &ad); } /** @@ -844,34 +1245,141 @@ static int smack_file_lock(struct file *file, unsigned int cmd) * @cmd: what action to check * @arg: unused * + * Generally these operations are harmless. + * File locking operations present an obvious mechanism + * for passing information, so they require write access. + * * Returns 0 if current has access, error code otherwise */ static int smack_file_fcntl(struct file *file, unsigned int cmd, unsigned long arg) { - int rc; + struct smk_audit_info ad; + int rc = 0; + switch (cmd) { - case F_DUPFD: - case F_GETFD: - case F_GETFL: case F_GETLK: - case F_GETOWN: - case F_GETSIG: - rc = smk_curacc(file->f_security, MAY_READ); break; - case F_SETFD: - case F_SETFL: case F_SETLK: case F_SETLKW: + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + rc = smk_curacc(file->f_security, MAY_LOCK, &ad); + break; case F_SETOWN: case F_SETSIG: - rc = smk_curacc(file->f_security, MAY_WRITE); + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + rc = smk_curacc(file->f_security, MAY_WRITE, &ad); break; default: - rc = smk_curacc(file->f_security, MAY_READWRITE); + break; + } + + return rc; +} + +/** + * smack_mmap_file : + * Check permissions for a mmap operation. The @file may be NULL, e.g. + * if mapping anonymous memory. + * @file contains the file structure for file to map (may be NULL). + * @reqprot contains the protection requested by the application. + * @prot contains the protection that will be applied by the kernel. + * @flags contains the operational flags. + * Return 0 if permission is granted. + */ +static int smack_mmap_file(struct file *file, + unsigned long reqprot, unsigned long prot, + unsigned long flags) +{ + struct smack_known *skp; + struct smack_known *mkp; + struct smack_rule *srp; + struct task_smack *tsp; + char *osmack; + struct inode_smack *isp; + int may; + int mmay; + int tmay; + int rc; + + if (file == NULL) + return 0; + + isp = file_inode(file)->i_security; + if (isp->smk_mmap == NULL) + return 0; + mkp = isp->smk_mmap; + + tsp = current_security(); + skp = smk_of_current(); + rc = 0; + + rcu_read_lock(); + /* + * For each Smack rule associated with the subject + * label verify that the SMACK64MMAP also has access + * to that rule's object label. + */ + list_for_each_entry_rcu(srp, &skp->smk_rules, list) { + osmack = srp->smk_object; + /* + * Matching labels always allows access. + */ + if (mkp->smk_known == osmack) + continue; + /* + * If there is a matching local rule take + * that into account as well. + */ + may = smk_access_entry(srp->smk_subject->smk_known, osmack, + &tsp->smk_rules); + if (may == -ENOENT) + may = srp->smk_access; + else + may &= srp->smk_access; + /* + * If may is zero the SMACK64MMAP subject can't + * possibly have less access. + */ + if (may == 0) + continue; + + /* + * Fetch the global list entry. + * If there isn't one a SMACK64MMAP subject + * can't have as much access as current. + */ + mmay = smk_access_entry(mkp->smk_known, osmack, + &mkp->smk_rules); + if (mmay == -ENOENT) { + rc = -EACCES; + break; + } + /* + * If there is a local entry it modifies the + * potential access, too. + */ + tmay = smk_access_entry(mkp->smk_known, osmack, + &tsp->smk_rules); + if (tmay != -ENOENT) + mmay &= tmay; + + /* + * If there is any access available to current that is + * not available to a SMACK64MMAP subject + * deny access. + */ + if ((may | mmay) != mmay) { + rc = -EACCES; + break; + } } + rcu_read_unlock(); + return rc; } @@ -884,7 +1392,9 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd, */ static int smack_file_set_fowner(struct file *file) { - file->f_security = current->security; + struct smack_known *skp = smk_of_current(); + + file->f_security = skp->smk_known; return 0; } @@ -902,16 +1412,26 @@ static int smack_file_set_fowner(struct file *file) static int smack_file_send_sigiotask(struct task_struct *tsk, struct fown_struct *fown, int signum) { + struct smack_known *skp; + struct smack_known *tkp = smk_of_task(tsk->cred->security); struct file *file; int rc; + struct smk_audit_info ad; /* * struct fown_struct is never outside the context of a struct file */ file = container_of(fown, struct file, f_owner); - rc = smk_access(file->f_security, tsk->security, MAY_WRITE); - if (rc != 0 && __capable(tsk, CAP_MAC_OVERRIDE)) - return 0; + + /* we don't log here as rc can be overriden */ + skp = smk_find_entry(file->f_security); + rc = smk_access(skp, tkp->smk_known, MAY_WRITE, NULL); + if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE)) + rc = 0; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, tsk); + smack_log(file->f_security, tkp->smk_known, MAY_WRITE, rc, &ad); return rc; } @@ -924,7 +1444,10 @@ static int smack_file_send_sigiotask(struct task_struct *tsk, static int smack_file_receive(struct file *file) { int may = 0; + struct smk_audit_info ad; + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); /* * This code relies on bitmasks. */ @@ -933,7 +1456,38 @@ static int smack_file_receive(struct file *file) if (file->f_mode & FMODE_WRITE) may |= MAY_WRITE; - return smk_curacc(file->f_security, may); + return smk_curacc(file->f_security, may, &ad); +} + +/** + * smack_file_open - Smack dentry open processing + * @file: the object + * @cred: task credential + * + * Set the security blob in the file structure. + * Allow the open only if the task has read access. There are + * many read operations (e.g. fstat) that you can do with an + * fd even if you have the file open write-only. + * + * Returns 0 + */ +static int smack_file_open(struct file *file, const struct cred *cred) +{ + struct task_smack *tsp = cred->security; + struct inode_smack *isp = file_inode(file)->i_security; + struct smk_audit_info ad; + int rc; + + if (smack_privileged(CAP_MAC_OVERRIDE)) + return 0; + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_PATH); + smk_ad_setfield_u_fs_path(&ad, file->f_path); + rc = smk_access(tsp->smk_task, isp->smk_inode, MAY_READ, &ad); + if (rc == 0) + file->f_security = isp->smk_inode; + + return rc; } /* @@ -941,33 +1495,155 @@ static int smack_file_receive(struct file *file) */ /** - * smack_task_alloc_security - "allocate" a task blob - * @tsk: the task in need of a blob + * smack_cred_alloc_blank - "allocate" blank task-level security credentials + * @new: the new credentials + * @gfp: the atomicity of any memory allocations * - * Smack isn't using copies of blobs. Everyone - * points to an immutable list. No alloc required. - * No data copy required. + * Prepare a blank set of credentials for modification. This must allocate all + * the memory the LSM module might require such that cred_transfer() can + * complete without error. + */ +static int smack_cred_alloc_blank(struct cred *cred, gfp_t gfp) +{ + struct task_smack *tsp; + + tsp = new_task_smack(NULL, NULL, gfp); + if (tsp == NULL) + return -ENOMEM; + + cred->security = tsp; + + return 0; +} + + +/** + * smack_cred_free - "free" task-level security credentials + * @cred: the credentials in question * - * Always returns 0 */ -static int smack_task_alloc_security(struct task_struct *tsk) +static void smack_cred_free(struct cred *cred) { - tsk->security = current->security; + struct task_smack *tsp = cred->security; + struct smack_rule *rp; + struct list_head *l; + struct list_head *n; + if (tsp == NULL) + return; + cred->security = NULL; + + list_for_each_safe(l, n, &tsp->smk_rules) { + rp = list_entry(l, struct smack_rule, list); + list_del(&rp->list); + kfree(rp); + } + kfree(tsp); +} + +/** + * smack_cred_prepare - prepare new set of credentials for modification + * @new: the new credentials + * @old: the original credentials + * @gfp: the atomicity of any memory allocations + * + * Prepare a new set of credentials for modification. + */ +static int smack_cred_prepare(struct cred *new, const struct cred *old, + gfp_t gfp) +{ + struct task_smack *old_tsp = old->security; + struct task_smack *new_tsp; + int rc; + + new_tsp = new_task_smack(old_tsp->smk_task, old_tsp->smk_task, gfp); + if (new_tsp == NULL) + return -ENOMEM; + + rc = smk_copy_rules(&new_tsp->smk_rules, &old_tsp->smk_rules, gfp); + if (rc != 0) + return rc; + + new->security = new_tsp; return 0; } /** - * smack_task_free_security - "free" a task blob - * @task: the task with the blob + * smack_cred_transfer - Transfer the old credentials to the new credentials + * @new: the new credentials + * @old: the original credentials * - * Smack isn't using copies of blobs. Everyone - * points to an immutable list. The blobs never go away. - * There is no leak here. + * Fill in a set of blank credentials from another set of credentials. */ -static void smack_task_free_security(struct task_struct *task) +static void smack_cred_transfer(struct cred *new, const struct cred *old) { - task->security = NULL; + struct task_smack *old_tsp = old->security; + struct task_smack *new_tsp = new->security; + + new_tsp->smk_task = old_tsp->smk_task; + new_tsp->smk_forked = old_tsp->smk_task; + mutex_init(&new_tsp->smk_rules_lock); + INIT_LIST_HEAD(&new_tsp->smk_rules); + + + /* cbs copy rule list */ +} + +/** + * smack_kernel_act_as - Set the subjective context in a set of credentials + * @new: points to the set of credentials to be modified. + * @secid: specifies the security ID to be set + * + * Set the security data for a kernel service. + */ +static int smack_kernel_act_as(struct cred *new, u32 secid) +{ + struct task_smack *new_tsp = new->security; + struct smack_known *skp = smack_from_secid(secid); + + if (skp == NULL) + return -EINVAL; + + new_tsp->smk_task = skp; + return 0; +} + +/** + * smack_kernel_create_files_as - Set the file creation label in a set of creds + * @new: points to the set of credentials to be modified + * @inode: points to the inode to use as a reference + * + * Set the file creation context in a set of credentials to the same + * as the objective context of the specified inode + */ +static int smack_kernel_create_files_as(struct cred *new, + struct inode *inode) +{ + struct inode_smack *isp = inode->i_security; + struct task_smack *tsp = new->security; + + tsp->smk_forked = smk_find_entry(isp->smk_inode); + tsp->smk_task = tsp->smk_forked; + return 0; +} + +/** + * smk_curacc_on_task - helper to log task related access + * @p: the task object + * @access: the access requested + * @caller: name of the calling function for audit + * + * Return 0 if access is permitted + */ +static int smk_curacc_on_task(struct task_struct *p, int access, + const char *caller) +{ + struct smk_audit_info ad; + struct smack_known *skp = smk_of_task(task_security(p)); + + smk_ad_init(&ad, caller, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); + return smk_curacc(skp->smk_known, access, &ad); } /** @@ -979,7 +1655,7 @@ static void smack_task_free_security(struct task_struct *task) */ static int smack_task_setpgid(struct task_struct *p, pid_t pgid) { - return smk_curacc(p->security, MAY_WRITE); + return smk_curacc_on_task(p, MAY_WRITE, __func__); } /** @@ -990,7 +1666,7 @@ static int smack_task_setpgid(struct task_struct *p, pid_t pgid) */ static int smack_task_getpgid(struct task_struct *p) { - return smk_curacc(p->security, MAY_READ); + return smk_curacc_on_task(p, MAY_READ, __func__); } /** @@ -1001,7 +1677,7 @@ static int smack_task_getpgid(struct task_struct *p) */ static int smack_task_getsid(struct task_struct *p) { - return smk_curacc(p->security, MAY_READ); + return smk_curacc_on_task(p, MAY_READ, __func__); } /** @@ -1013,7 +1689,9 @@ static int smack_task_getsid(struct task_struct *p) */ static void smack_task_getsecid(struct task_struct *p, u32 *secid) { - *secid = smack_to_secid(p->security); + struct smack_known *skp = smk_of_task(task_security(p)); + + *secid = skp->smk_secid; } /** @@ -1029,7 +1707,7 @@ static int smack_task_setnice(struct task_struct *p, int nice) rc = cap_task_setnice(p, nice); if (rc == 0) - rc = smk_curacc(p->security, MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE, __func__); return rc; } @@ -1046,7 +1724,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio) rc = cap_task_setioprio(p, ioprio); if (rc == 0) - rc = smk_curacc(p->security, MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE, __func__); return rc; } @@ -1058,7 +1736,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio) */ static int smack_task_getioprio(struct task_struct *p) { - return smk_curacc(p->security, MAY_READ); + return smk_curacc_on_task(p, MAY_READ, __func__); } /** @@ -1069,14 +1747,13 @@ static int smack_task_getioprio(struct task_struct *p) * * Return 0 if read access is permitted */ -static int smack_task_setscheduler(struct task_struct *p, int policy, - struct sched_param *lp) +static int smack_task_setscheduler(struct task_struct *p) { int rc; - rc = cap_task_setscheduler(p, policy, lp); + rc = cap_task_setscheduler(p); if (rc == 0) - rc = smk_curacc(p->security, MAY_WRITE); + rc = smk_curacc_on_task(p, MAY_WRITE, __func__); return rc; } @@ -1088,7 +1765,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy, */ static int smack_task_getscheduler(struct task_struct *p) { - return smk_curacc(p->security, MAY_READ); + return smk_curacc_on_task(p, MAY_READ, __func__); } /** @@ -1099,7 +1776,7 @@ static int smack_task_getscheduler(struct task_struct *p) */ static int smack_task_movememory(struct task_struct *p) { - return smk_curacc(p->security, MAY_WRITE); + return smk_curacc_on_task(p, MAY_WRITE, __func__); } /** @@ -1117,71 +1794,59 @@ static int smack_task_movememory(struct task_struct *p) static int smack_task_kill(struct task_struct *p, struct siginfo *info, int sig, u32 secid) { - /* - * Special cases where signals really ought to go through - * in spite of policy. Stephen Smalley suggests it may - * make sense to change the caller so that it doesn't - * bother with the LSM hook in these cases. - */ - if (info != SEND_SIG_NOINFO && - (is_si_special(info) || SI_FROMKERNEL(info))) - return 0; + struct smk_audit_info ad; + struct smack_known *skp; + struct smack_known *tkp = smk_of_task(task_security(p)); + + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_TASK); + smk_ad_setfield_u_tsk(&ad, p); /* * Sending a signal requires that the sender * can write the receiver. */ if (secid == 0) - return smk_curacc(p->security, MAY_WRITE); + return smk_curacc(tkp->smk_known, MAY_WRITE, &ad); /* * If the secid isn't 0 we're dealing with some USB IO * specific behavior. This is not clean. For one thing * we can't take privilege into account. */ - return smk_access(smack_from_secid(secid), p->security, MAY_WRITE); + skp = smack_from_secid(secid); + return smk_access(skp, tkp->smk_known, MAY_WRITE, &ad); } /** * smack_task_wait - Smack access check for waiting * @p: task to wait for * - * Returns 0 if current can wait for p, error code otherwise + * Returns 0 */ static int smack_task_wait(struct task_struct *p) { - int rc; - - rc = smk_access(current->security, p->security, MAY_WRITE); - if (rc == 0) - return 0; - /* - * Allow the operation to succeed if either task - * has privilege to perform operations that might - * account for the smack labels having gotten to - * be different in the first place. - * - * This breaks the strict subjet/object access - * control ideal, taking the object's privilege - * state into account in the decision as well as - * the smack value. + * Allow the operation to succeed. + * Zombies are bad. + * In userless environments (e.g. phones) programs + * get marked with SMACK64EXEC and even if the parent + * and child shouldn't be talking the parent still + * may expect to know when the child exits. */ - if (capable(CAP_MAC_OVERRIDE) || __capable(p, CAP_MAC_OVERRIDE)) - return 0; - - return rc; + return 0; } /** * smack_task_to_inode - copy task smack into the inode blob * @p: task to copy from - * inode: inode to copy to + * @inode: inode to copy to * * Sets the smack pointer in the inode security blob */ static void smack_task_to_inode(struct task_struct *p, struct inode *inode) { struct inode_smack *isp = inode->i_security; - isp->smk_inode = p->security; + struct smack_known *skp = smk_of_task(task_security(p)); + + isp->smk_inode = skp->smk_known; } /* @@ -1192,7 +1857,7 @@ static void smack_task_to_inode(struct task_struct *p, struct inode *inode) * smack_sk_alloc_security - Allocate a socket blob * @sk: the socket * @family: unused - * @priority: memory allocation priority + * @gfp_flags: memory allocation flags * * Assign Smack pointers to current * @@ -1200,16 +1865,16 @@ static void smack_task_to_inode(struct task_struct *p, struct inode *inode) */ static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags) { - char *csp = current->security; + struct smack_known *skp = smk_of_current(); struct socket_smack *ssp; ssp = kzalloc(sizeof(struct socket_smack), gfp_flags); if (ssp == NULL) return -ENOMEM; - ssp->smk_in = csp; - ssp->smk_out = csp; - ssp->smk_packet[0] = '\0'; + ssp->smk_in = skp; + ssp->smk_out = skp; + ssp->smk_packet = NULL; sk->sk_security = ssp; @@ -1228,92 +1893,273 @@ static void smack_sk_free_security(struct sock *sk) } /** - * smack_set_catset - convert a capset to netlabel mls categories - * @catset: the Smack categories - * @sap: where to put the netlabel categories +* smack_host_label - check host based restrictions +* @sip: the object end +* +* looks for host based access restrictions +* +* This version will only be appropriate for really small sets of single label +* hosts. The caller is responsible for ensuring that the RCU read lock is +* taken before calling this function. +* +* Returns the label of the far end or NULL if it's not special. +*/ +static char *smack_host_label(struct sockaddr_in *sip) +{ + struct smk_netlbladdr *snp; + struct in_addr *siap = &sip->sin_addr; + + if (siap->s_addr == 0) + return NULL; + + list_for_each_entry_rcu(snp, &smk_netlbladdr_list, list) + /* + * we break after finding the first match because + * the list is sorted from longest to shortest mask + * so we have found the most specific match + */ + if ((&snp->smk_host.sin_addr)->s_addr == + (siap->s_addr & (&snp->smk_mask)->s_addr)) { + /* we have found the special CIPSO option */ + if (snp->smk_label == smack_cipso_option) + return NULL; + return snp->smk_label; + } + + return NULL; +} + +/** + * smack_netlabel - Set the secattr on a socket + * @sk: the socket + * @labeled: socket label scheme + * + * Convert the outbound smack value (smk_out) to a + * secattr and attach it to the socket. * - * Allocates and fills attr.mls.cat + * Returns 0 on success or an error code */ -static void smack_set_catset(char *catset, struct netlbl_lsm_secattr *sap) +static int smack_netlabel(struct sock *sk, int labeled) { - unsigned char *cp; - unsigned char m; - int cat; - int rc; - int byte; + struct smack_known *skp; + struct socket_smack *ssp = sk->sk_security; + int rc = 0; - if (catset == 0) - return; + /* + * Usually the netlabel code will handle changing the + * packet labeling based on the label. + * The case of a single label host is different, because + * a single label host should never get a labeled packet + * even though the label is usually associated with a packet + * label. + */ + local_bh_disable(); + bh_lock_sock_nested(sk); + + if (ssp->smk_out == smack_net_ambient || + labeled == SMACK_UNLABELED_SOCKET) + netlbl_sock_delattr(sk); + else { + skp = ssp->smk_out; + rc = netlbl_sock_setattr(sk, sk->sk_family, &skp->smk_netlabel); + } - sap->flags |= NETLBL_SECATTR_MLS_CAT; - sap->attr.mls.cat = netlbl_secattr_catmap_alloc(GFP_ATOMIC); - sap->attr.mls.cat->startbit = 0; + bh_unlock_sock(sk); + local_bh_enable(); - for (cat = 1, cp = catset, byte = 0; byte < SMK_LABELLEN; cp++, byte++) - for (m = 0x80; m != 0; m >>= 1, cat++) { - if ((m & *cp) == 0) - continue; - rc = netlbl_secattr_catmap_setbit(sap->attr.mls.cat, - cat, GFP_ATOMIC); - } + return rc; } /** - * smack_to_secattr - fill a secattr from a smack value - * @smack: the smack value - * @nlsp: where the result goes + * smack_netlbel_send - Set the secattr on a socket and perform access checks + * @sk: the socket + * @sap: the destination address + * + * Set the correct secattr for the given socket based on the destination + * address and perform any outbound access checks needed. + * + * Returns 0 on success or an error code. * - * Casey says that CIPSO is good enough for now. - * It can be used to effect. - * It can also be abused to effect when necessary. - * Appologies to the TSIG group in general and GW in particular. */ -static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp) +static int smack_netlabel_send(struct sock *sk, struct sockaddr_in *sap) { - struct smack_cipso cipso; + struct smack_known *skp; int rc; + int sk_lbl; + char *hostsp; + struct socket_smack *ssp = sk->sk_security; + struct smk_audit_info ad; + + rcu_read_lock(); + hostsp = smack_host_label(sap); + if (hostsp != NULL) { +#ifdef CONFIG_AUDIT + struct lsm_network_audit net; + + smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); + ad.a.u.net->family = sap->sin_family; + ad.a.u.net->dport = sap->sin_port; + ad.a.u.net->v4info.daddr = sap->sin_addr.s_addr; +#endif + sk_lbl = SMACK_UNLABELED_SOCKET; + skp = ssp->smk_out; + rc = smk_access(skp, hostsp, MAY_WRITE, &ad); + } else { + sk_lbl = SMACK_CIPSO_SOCKET; + rc = 0; + } + rcu_read_unlock(); + if (rc != 0) + return rc; - switch (smack_net_nltype) { - case NETLBL_NLTYPE_CIPSOV4: - nlsp->domain = kstrdup(smack, GFP_ATOMIC); - nlsp->flags = NETLBL_SECATTR_DOMAIN | NETLBL_SECATTR_MLS_LVL; + return smack_netlabel(sk, sk_lbl); +} - rc = smack_to_cipso(smack, &cipso); - if (rc == 0) { - nlsp->attr.mls.lvl = cipso.smk_level; - smack_set_catset(cipso.smk_catset, nlsp); - } else { - nlsp->attr.mls.lvl = smack_cipso_direct; - smack_set_catset(smack, nlsp); +/** + * smk_ipv6_port_label - Smack port access table management + * @sock: socket + * @address: address + * + * Create or update the port list entry + */ +static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address) +{ + struct sock *sk = sock->sk; + struct sockaddr_in6 *addr6; + struct socket_smack *ssp = sock->sk->sk_security; + struct smk_port_label *spp; + unsigned short port = 0; + + if (address == NULL) { + /* + * This operation is changing the Smack information + * on the bound socket. Take the changes to the port + * as well. + */ + list_for_each_entry(spp, &smk_ipv6_port_list, list) { + if (sk != spp->smk_sock) + continue; + spp->smk_in = ssp->smk_in; + spp->smk_out = ssp->smk_out; + return; } - break; - default: - break; + /* + * A NULL address is only used for updating existing + * bound entries. If there isn't one, it's OK. + */ + return; } + + addr6 = (struct sockaddr_in6 *)address; + port = ntohs(addr6->sin6_port); + /* + * This is a special case that is safely ignored. + */ + if (port == 0) + return; + + /* + * Look for an existing port list entry. + * This is an indication that a port is getting reused. + */ + list_for_each_entry(spp, &smk_ipv6_port_list, list) { + if (spp->smk_port != port) + continue; + spp->smk_port = port; + spp->smk_sock = sk; + spp->smk_in = ssp->smk_in; + spp->smk_out = ssp->smk_out; + return; + } + + /* + * A new port entry is required. + */ + spp = kzalloc(sizeof(*spp), GFP_KERNEL); + if (spp == NULL) + return; + + spp->smk_port = port; + spp->smk_sock = sk; + spp->smk_in = ssp->smk_in; + spp->smk_out = ssp->smk_out; + + list_add(&spp->list, &smk_ipv6_port_list); + return; } /** - * smack_netlabel - Set the secattr on a socket - * @sk: the socket + * smk_ipv6_port_check - check Smack port access + * @sock: socket + * @address: address * - * Convert the outbound smack value (smk_out) to a - * secattr and attach it to the socket. - * - * Returns 0 on success or an error code + * Create or update the port list entry */ -static int smack_netlabel(struct sock *sk) +static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address, + int act) { - struct socket_smack *ssp; - struct netlbl_lsm_secattr secattr; - int rc; + __be16 *bep; + __be32 *be32p; + struct smk_port_label *spp; + struct socket_smack *ssp = sk->sk_security; + struct smack_known *skp; + unsigned short port = 0; + char *object; + struct smk_audit_info ad; +#ifdef CONFIG_AUDIT + struct lsm_network_audit net; +#endif + + if (act == SMK_RECEIVING) { + skp = smack_net_ambient; + object = ssp->smk_in->smk_known; + } else { + skp = ssp->smk_out; + object = smack_net_ambient->smk_known; + } - ssp = sk->sk_security; - netlbl_secattr_init(&secattr); - smack_to_secattr(ssp->smk_out, &secattr); - rc = netlbl_sock_setattr(sk, &secattr); - netlbl_secattr_destroy(&secattr); + /* + * Get the IP address and port from the address. + */ + port = ntohs(address->sin6_port); + bep = (__be16 *)(&address->sin6_addr); + be32p = (__be32 *)(&address->sin6_addr); - return rc; + /* + * It's remote, so port lookup does no good. + */ + if (be32p[0] || be32p[1] || be32p[2] || bep[6] || ntohs(bep[7]) != 1) + goto auditout; + + /* + * It's local so the send check has to have passed. + */ + if (act == SMK_RECEIVING) { + skp = &smack_known_web; + goto auditout; + } + + list_for_each_entry(spp, &smk_ipv6_port_list, list) { + if (spp->smk_port != port) + continue; + object = spp->smk_in->smk_known; + if (act == SMK_CONNECTING) + ssp->smk_packet = spp->smk_out; + break; + } + +auditout: + +#ifdef CONFIG_AUDIT + smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); + ad.a.u.net->family = sk->sk_family; + ad.a.u.net->dport = port; + if (act == SMK_RECEIVING) + ad.a.u.net->v6info.saddr = address->sin6_addr; + else + ad.a.u.net->v6info.daddr = address->sin6_addr; +#endif + return smk_access(skp, object, MAY_WRITE, &ad); } /** @@ -1331,21 +2177,22 @@ static int smack_netlabel(struct sock *sk) static int smack_inode_setsecurity(struct inode *inode, const char *name, const void *value, size_t size, int flags) { - char *sp; + struct smack_known *skp; struct inode_smack *nsp = inode->i_security; struct socket_smack *ssp; struct socket *sock; int rc = 0; - if (value == NULL || size > SMK_LABELLEN) - return -EACCES; + if (value == NULL || size > SMK_LONGLABEL || size == 0) + return -EINVAL; - sp = smk_import(value, size); - if (sp == NULL) + skp = smk_import_entry(value, size); + if (skp == NULL) return -EINVAL; if (strcmp(name, XATTR_SMACK_SUFFIX) == 0) { - nsp->smk_inode = sp; + nsp->smk_inode = skp->smk_known; + nsp->smk_flags |= SMK_INODE_INSTANT; return 0; } /* @@ -1361,16 +2208,22 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name, ssp = sock->sk->sk_security; if (strcmp(name, XATTR_SMACK_IPIN) == 0) - ssp->smk_in = sp; + ssp->smk_in = skp; else if (strcmp(name, XATTR_SMACK_IPOUT) == 0) { - ssp->smk_out = sp; - rc = smack_netlabel(sock->sk); - if (rc != 0) - printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", - __func__, -rc); + ssp->smk_out = skp; + if (sock->sk->sk_family == PF_INET) { + rc = smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); + if (rc != 0) + printk(KERN_WARNING + "Smack: \"%s\" netlbl error %d.\n", + __func__, -rc); + } } else return -EOPNOTSUPP; + if (sock->sk->sk_family == PF_INET6) + smk_ipv6_port_label(sock, NULL); + return 0; } @@ -1394,7 +2247,60 @@ static int smack_socket_post_create(struct socket *sock, int family, /* * Set the outbound netlbl. */ - return smack_netlabel(sock->sk); + return smack_netlabel(sock->sk, SMACK_CIPSO_SOCKET); +} + +/** + * smack_socket_bind - record port binding information. + * @sock: the socket + * @address: the port address + * @addrlen: size of the address + * + * Records the label bound to a port. + * + * Returns 0 + */ +static int smack_socket_bind(struct socket *sock, struct sockaddr *address, + int addrlen) +{ + if (sock->sk != NULL && sock->sk->sk_family == PF_INET6) + smk_ipv6_port_label(sock, address); + + return 0; +} + +/** + * smack_socket_connect - connect access check + * @sock: the socket + * @sap: the other end + * @addrlen: size of sap + * + * Verifies that a connection may be possible + * + * Returns 0 on success, and error code otherwise + */ +static int smack_socket_connect(struct socket *sock, struct sockaddr *sap, + int addrlen) +{ + int rc = 0; + + if (sock->sk == NULL) + return 0; + + switch (sock->sk->sk_family) { + case PF_INET: + if (addrlen < sizeof(struct sockaddr_in)) + return -EINVAL; + rc = smack_netlabel_send(sock->sk, (struct sockaddr_in *)sap); + break; + case PF_INET6: + if (addrlen < sizeof(struct sockaddr_in6)) + return -EINVAL; + rc = smk_ipv6_port_check(sock->sk, (struct sockaddr_in6 *)sap, + SMK_CONNECTING); + break; + } + return rc; } /** @@ -1425,7 +2331,9 @@ static int smack_flags_to_may(int flags) */ static int smack_msg_msg_alloc_security(struct msg_msg *msg) { - msg->security = current->security; + struct smack_known *skp = smk_of_current(); + + msg->security = skp->smk_known; return 0; } @@ -1460,8 +2368,9 @@ static char *smack_of_shm(struct shmid_kernel *shp) static int smack_shm_alloc_security(struct shmid_kernel *shp) { struct kern_ipc_perm *isp = &shp->shm_perm; + struct smack_known *skp = smk_of_current(); - isp->security = current->security; + isp->security = skp->smk_known; return 0; } @@ -1479,6 +2388,25 @@ static void smack_shm_free_security(struct shmid_kernel *shp) } /** + * smk_curacc_shm : check if current has access on shm + * @shp : the object + * @access : access requested + * + * Returns 0 if current has the requested access, error code otherwise + */ +static int smk_curacc_shm(struct shmid_kernel *shp, int access) +{ + char *ssp = smack_of_shm(shp); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = shp->shm_perm.id; +#endif + return smk_curacc(ssp, access, &ad); +} + +/** * smack_shm_associate - Smack access check for shm * @shp: the object * @shmflg: access requested @@ -1487,11 +2415,10 @@ static void smack_shm_free_security(struct shmid_kernel *shp) */ static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) { - char *ssp = smack_of_shm(shp); int may; may = smack_flags_to_may(shmflg); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1503,7 +2430,6 @@ static int smack_shm_associate(struct shmid_kernel *shp, int shmflg) */ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) { - char *ssp; int may; switch (cmd) { @@ -1526,9 +2452,7 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) default: return -EINVAL; } - - ssp = smack_of_shm(shp); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1542,11 +2466,10 @@ static int smack_shm_shmctl(struct shmid_kernel *shp, int cmd) static int smack_shm_shmat(struct shmid_kernel *shp, char __user *shmaddr, int shmflg) { - char *ssp = smack_of_shm(shp); int may; may = smack_flags_to_may(shmflg); - return smk_curacc(ssp, may); + return smk_curacc_shm(shp, may); } /** @@ -1569,8 +2492,9 @@ static char *smack_of_sem(struct sem_array *sma) static int smack_sem_alloc_security(struct sem_array *sma) { struct kern_ipc_perm *isp = &sma->sem_perm; + struct smack_known *skp = smk_of_current(); - isp->security = current->security; + isp->security = skp->smk_known; return 0; } @@ -1588,6 +2512,25 @@ static void smack_sem_free_security(struct sem_array *sma) } /** + * smk_curacc_sem : check if current has access on sem + * @sma : the object + * @access : access requested + * + * Returns 0 if current has the requested access, error code otherwise + */ +static int smk_curacc_sem(struct sem_array *sma, int access) +{ + char *ssp = smack_of_sem(sma); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = sma->sem_perm.id; +#endif + return smk_curacc(ssp, access, &ad); +} + +/** * smack_sem_associate - Smack access check for sem * @sma: the object * @semflg: access requested @@ -1596,11 +2539,10 @@ static void smack_sem_free_security(struct sem_array *sma) */ static int smack_sem_associate(struct sem_array *sma, int semflg) { - char *ssp = smack_of_sem(sma); int may; may = smack_flags_to_may(semflg); - return smk_curacc(ssp, may); + return smk_curacc_sem(sma, may); } /** @@ -1612,7 +2554,6 @@ static int smack_sem_associate(struct sem_array *sma, int semflg) */ static int smack_sem_semctl(struct sem_array *sma, int cmd) { - char *ssp; int may; switch (cmd) { @@ -1641,8 +2582,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) return -EINVAL; } - ssp = smack_of_sem(sma); - return smk_curacc(ssp, may); + return smk_curacc_sem(sma, may); } /** @@ -1659,9 +2599,7 @@ static int smack_sem_semctl(struct sem_array *sma, int cmd) static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, unsigned nsops, int alter) { - char *ssp = smack_of_sem(sma); - - return smk_curacc(ssp, MAY_READWRITE); + return smk_curacc_sem(sma, MAY_READWRITE); } /** @@ -1673,8 +2611,9 @@ static int smack_sem_semop(struct sem_array *sma, struct sembuf *sops, static int smack_msg_queue_alloc_security(struct msg_queue *msq) { struct kern_ipc_perm *kisp = &msq->q_perm; + struct smack_known *skp = smk_of_current(); - kisp->security = current->security; + kisp->security = skp->smk_known; return 0; } @@ -1703,6 +2642,25 @@ static char *smack_of_msq(struct msg_queue *msq) } /** + * smk_curacc_msq : helper to check if current has access on msq + * @msq : the msq + * @access : access requested + * + * return 0 if current has access, error otherwise + */ +static int smk_curacc_msq(struct msg_queue *msq, int access) +{ + char *msp = smack_of_msq(msq); + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = msq->q_perm.id; +#endif + return smk_curacc(msp, access, &ad); +} + +/** * smack_msg_queue_associate - Smack access check for msg_queue * @msq: the object * @msqflg: access requested @@ -1711,11 +2669,10 @@ static char *smack_of_msq(struct msg_queue *msq) */ static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) { - char *msp = smack_of_msq(msq); int may; may = smack_flags_to_may(msqflg); - return smk_curacc(msp, may); + return smk_curacc_msq(msq, may); } /** @@ -1727,7 +2684,6 @@ static int smack_msg_queue_associate(struct msg_queue *msq, int msqflg) */ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) { - char *msp; int may; switch (cmd) { @@ -1749,8 +2705,7 @@ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) return -EINVAL; } - msp = smack_of_msq(msq); - return smk_curacc(msp, may); + return smk_curacc_msq(msq, may); } /** @@ -1764,11 +2719,10 @@ static int smack_msg_queue_msgctl(struct msg_queue *msq, int cmd) static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg) { - char *msp = smack_of_msq(msq); - int rc; + int may; - rc = smack_flags_to_may(msqflg); - return smk_curacc(msp, rc); + may = smack_flags_to_may(msqflg); + return smk_curacc_msq(msq, may); } /** @@ -1784,9 +2738,7 @@ static int smack_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, struct task_struct *target, long type, int mode) { - char *msp = smack_of_msq(msq); - - return smk_curacc(msp, MAY_READWRITE); + return smk_curacc_msq(msq, MAY_READWRITE); } /** @@ -1799,36 +2751,31 @@ static int smack_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg, static int smack_ipc_permission(struct kern_ipc_perm *ipp, short flag) { char *isp = ipp->security; - int may; + int may = smack_flags_to_may(flag); + struct smk_audit_info ad; - may = smack_flags_to_may(flag); - return smk_curacc(isp, may); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_IPC); + ad.a.u.ipc_id = ipp->id; +#endif + return smk_curacc(isp, may, &ad); } -/* module stacking operations */ - /** - * smack_register_security - stack capability module - * @name: module name - * @ops: module operations - ignored - * - * Allow the capability module to register. + * smack_ipc_getsecid - Extract smack security id + * @ipp: the object permissions + * @secid: where result will be saved */ -static int smack_register_security(const char *name, - struct security_operations *ops) +static void smack_ipc_getsecid(struct kern_ipc_perm *ipp, u32 *secid) { - if (strcmp(name, "capability") != 0) - return -EINVAL; + char *smack = ipp->security; - printk(KERN_INFO "%s: Registering secondary module %s\n", - __func__, name); - - return 0; + *secid = smack_to_secid(smack); } /** * smack_d_instantiate - Make sure the blob is correct on an inode - * @opt_dentry: unused + * @opt_dentry: dentry where inode will be attached * @inode: the object * * Set the inode's security blob if it hasn't been done already. @@ -1838,9 +2785,12 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) struct super_block *sbp; struct superblock_smack *sbsp; struct inode_smack *isp; - char *csp = current->security; - char *fetched; + struct smack_known *skp; + struct smack_known *ckp = smk_of_current(); char *final; + char trattr[TRANS_TRUE_SIZE]; + int transflag = 0; + int rc; struct dentry *dp; if (inode == NULL) @@ -1865,6 +2815,27 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) final = sbsp->smk_default; /* + * If this is the root inode the superblock + * may be in the process of initialization. + * If that is the case use the root value out + * of the superblock. + */ + if (opt_dentry->d_parent == opt_dentry) { + if (sbp->s_magic == CGROUP_SUPER_MAGIC) { + /* + * The cgroup filesystem is never mounted, + * so there's no opportunity to set the mount + * options. + */ + sbsp->smk_root = smack_known_star.smk_known; + sbsp->smk_default = smack_known_star.smk_known; + } + isp->smk_inode = sbsp->smk_root; + isp->smk_flags |= SMK_INODE_INSTANT; + goto unlockandout; + } + + /* * This is pretty hackish. * Casey says that we shouldn't have to do * file system specific code, but it does help @@ -1872,16 +2843,20 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) */ switch (sbp->s_magic) { case SMACK_MAGIC: + case PIPEFS_MAGIC: + case SOCKFS_MAGIC: + case CGROUP_SUPER_MAGIC: /* - * Casey says that it's a little embarassing + * Casey says that it's a little embarrassing * that the smack file system doesn't do * extended attributes. - */ - final = smack_known_star.smk_known; - break; - case PIPEFS_MAGIC: - /* + * * Casey says pipes are easy (?) + * + * Socket access is controlled by the socket + * structures associated with the task involved. + * + * Cgroupfs is special */ final = smack_known_star.smk_known; break; @@ -1891,13 +2866,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) * Programs that change smack have to treat the * pty with respect. */ - final = csp; - break; - case SOCKFS_MAGIC: - /* - * Casey says sockets get the smack of the task. - */ - final = csp; + final = ckp->smk_known; break; case PROC_SUPER_MAGIC: /* @@ -1924,7 +2893,16 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) /* * This isn't an understood special case. * Get the value from the xattr. - * + */ + + /* + * UNIX domain sockets use lower level socket data. + */ + if (S_ISSOCK(inode->i_mode)) { + final = smack_known_star.smk_known; + break; + } + /* * No xattr support means, alas, no SMACK label. * Use the aforeapplied default. * It would be curious if the label of the task @@ -1935,30 +2913,63 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode) /* * Get the dentry for xattr. */ - if (opt_dentry == NULL) { - dp = d_find_alias(inode); - if (dp == NULL) - break; - } else { - dp = dget(opt_dentry); - if (dp == NULL) - break; - } + dp = dget(opt_dentry); + skp = smk_fetch(XATTR_NAME_SMACK, inode, dp); + if (skp != NULL) + final = skp->smk_known; - fetched = smk_fetch(inode, dp); - if (fetched != NULL) - final = fetched; + /* + * Transmuting directory + */ + if (S_ISDIR(inode->i_mode)) { + /* + * If this is a new directory and the label was + * transmuted when the inode was initialized + * set the transmute attribute on the directory + * and mark the inode. + * + * If there is a transmute attribute on the + * directory mark the inode. + */ + if (isp->smk_flags & SMK_INODE_CHANGED) { + isp->smk_flags &= ~SMK_INODE_CHANGED; + rc = inode->i_op->setxattr(dp, + XATTR_NAME_SMACKTRANSMUTE, + TRANS_TRUE, TRANS_TRUE_SIZE, + 0); + } else { + rc = inode->i_op->getxattr(dp, + XATTR_NAME_SMACKTRANSMUTE, trattr, + TRANS_TRUE_SIZE); + if (rc >= 0 && strncmp(trattr, TRANS_TRUE, + TRANS_TRUE_SIZE) != 0) + rc = -EINVAL; + } + if (rc >= 0) + transflag = SMK_INODE_TRANSMUTE; + } + /* + * Don't let the exec or mmap label be "*" or "@". + */ + skp = smk_fetch(XATTR_NAME_SMACKEXEC, inode, dp); + if (skp == &smack_known_star || skp == &smack_known_web) + skp = NULL; + isp->smk_task = skp; + skp = smk_fetch(XATTR_NAME_SMACKMMAP, inode, dp); + if (skp == &smack_known_star || skp == &smack_known_web) + skp = NULL; + isp->smk_mmap = skp; dput(dp); break; } if (final == NULL) - isp->smk_inode = csp; + isp->smk_inode = ckp->smk_known; else isp->smk_inode = final; - isp->smk_flags |= SMK_INODE_INSTANT; + isp->smk_flags |= (SMK_INODE_INSTANT | transflag); unlockandout: mutex_unlock(&isp->smk_lock); @@ -1977,13 +2988,14 @@ unlockandout: */ static int smack_getprocattr(struct task_struct *p, char *name, char **value) { + struct smack_known *skp = smk_of_task(task_security(p)); char *cp; int slen; if (strcmp(name, "current") != 0) return -EINVAL; - cp = kstrdup(p->security, GFP_KERNEL); + cp = kstrdup(skp->smk_known, GFP_KERNEL); if (cp == NULL) return -ENOMEM; @@ -2007,10 +3019,9 @@ static int smack_getprocattr(struct task_struct *p, char *name, char **value) static int smack_setprocattr(struct task_struct *p, char *name, void *value, size_t size) { - char *newsmack; - - if (!__capable(p, CAP_MAC_ADMIN)) - return -EPERM; + struct task_smack *tsp; + struct cred *new; + struct smack_known *skp; /* * Changing another process' Smack value is too dangerous @@ -2019,36 +3030,80 @@ static int smack_setprocattr(struct task_struct *p, char *name, if (p != current) return -EPERM; - if (value == NULL || size == 0 || size >= SMK_LABELLEN) + if (!smack_privileged(CAP_MAC_ADMIN)) + return -EPERM; + + if (value == NULL || size == 0 || size >= SMK_LONGLABEL) return -EINVAL; if (strcmp(name, "current") != 0) return -EINVAL; - newsmack = smk_import(value, size); - if (newsmack == NULL) + skp = smk_import_entry(value, size); + if (skp == NULL) return -EINVAL; - p->security = newsmack; + /* + * No process is ever allowed the web ("@") label. + */ + if (skp == &smack_known_web) + return -EPERM; + + new = prepare_creds(); + if (new == NULL) + return -ENOMEM; + + tsp = new->security; + tsp->smk_task = skp; + + commit_creds(new); return size; } /** * smack_unix_stream_connect - Smack access on UDS - * @sock: one socket - * @other: the other socket + * @sock: one sock + * @other: the other sock * @newsk: unused * * Return 0 if a subject with the smack of sock could access * an object with the smack of other, otherwise an error code */ -static int smack_unix_stream_connect(struct socket *sock, - struct socket *other, struct sock *newsk) +static int smack_unix_stream_connect(struct sock *sock, + struct sock *other, struct sock *newsk) { - struct inode *sp = SOCK_INODE(sock); - struct inode *op = SOCK_INODE(other); + struct smack_known *skp; + struct smack_known *okp; + struct socket_smack *ssp = sock->sk_security; + struct socket_smack *osp = other->sk_security; + struct socket_smack *nsp = newsk->sk_security; + struct smk_audit_info ad; + int rc = 0; +#ifdef CONFIG_AUDIT + struct lsm_network_audit net; +#endif + + if (!smack_privileged(CAP_MAC_OVERRIDE)) { + skp = ssp->smk_out; + okp = osp->smk_out; +#ifdef CONFIG_AUDIT + smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); + smk_ad_setfield_u_net_sk(&ad, other); +#endif + rc = smk_access(skp, okp->smk_known, MAY_WRITE, &ad); + if (rc == 0) + rc = smk_access(okp, okp->smk_known, MAY_WRITE, NULL); + } + + /* + * Cross reference the peer labels for SO_PEERSEC. + */ + if (rc == 0) { + nsp->smk_packet = ssp->smk_out; + ssp->smk_packet = osp->smk_out; + } - return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_READWRITE); + return rc; } /** @@ -2061,62 +3116,189 @@ static int smack_unix_stream_connect(struct socket *sock, */ static int smack_unix_may_send(struct socket *sock, struct socket *other) { - struct inode *sp = SOCK_INODE(sock); - struct inode *op = SOCK_INODE(other); + struct socket_smack *ssp = sock->sk->sk_security; + struct socket_smack *osp = other->sk->sk_security; + struct smack_known *skp; + struct smk_audit_info ad; + +#ifdef CONFIG_AUDIT + struct lsm_network_audit net; + + smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); + smk_ad_setfield_u_net_sk(&ad, other->sk); +#endif + + if (smack_privileged(CAP_MAC_OVERRIDE)) + return 0; - return smk_access(smk_of_inode(sp), smk_of_inode(op), MAY_WRITE); + skp = ssp->smk_out; + return smk_access(skp, osp->smk_in->smk_known, MAY_WRITE, &ad); } /** - * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat - * pair to smack + * smack_socket_sendmsg - Smack check based on destination host + * @sock: the socket + * @msg: the message + * @size: the size of the message + * + * Return 0 if the current subject can write to the destination host. + * For IPv4 this is only a question if the destination is a single label host. + * For IPv6 this is a check against the label of the port. + */ +static int smack_socket_sendmsg(struct socket *sock, struct msghdr *msg, + int size) +{ + struct sockaddr_in *sip = (struct sockaddr_in *) msg->msg_name; + struct sockaddr_in6 *sap = (struct sockaddr_in6 *) msg->msg_name; + int rc = 0; + + /* + * Perfectly reasonable for this to be NULL + */ + if (sip == NULL) + return 0; + + switch (sip->sin_family) { + case AF_INET: + rc = smack_netlabel_send(sock->sk, sip); + break; + case AF_INET6: + rc = smk_ipv6_port_check(sock->sk, sap, SMK_SENDING); + break; + } + return rc; +} + +/** + * smack_from_secattr - Convert a netlabel attr.mls.lvl/attr.mls.cat pair to smack * @sap: netlabel secattr - * @sip: where to put the result + * @ssp: socket security information * - * Copies a smack label into sip + * Returns a pointer to a Smack label entry found on the label list. */ -static void smack_from_secattr(struct netlbl_lsm_secattr *sap, char *sip) +static struct smack_known *smack_from_secattr(struct netlbl_lsm_secattr *sap, + struct socket_smack *ssp) { - char smack[SMK_LABELLEN]; - int pcat; + struct smack_known *skp; + int found = 0; + int acat; + int kcat; - if ((sap->flags & NETLBL_SECATTR_MLS_LVL) == 0) { + if ((sap->flags & NETLBL_SECATTR_MLS_LVL) != 0) { /* + * Looks like a CIPSO packet. * If there are flags but no level netlabel isn't * behaving the way we expect it to. * + * Look it up in the label table * Without guidance regarding the smack value * for the packet fall back on the network * ambient value. */ - strncpy(sip, smack_net_ambient, SMK_MAXLEN); - return; - } - /* - * Get the categories, if any - */ - memset(smack, '\0', SMK_LABELLEN); - if ((sap->flags & NETLBL_SECATTR_MLS_CAT) != 0) - for (pcat = -1;;) { - pcat = netlbl_secattr_catmap_walk(sap->attr.mls.cat, - pcat + 1); - if (pcat < 0) + rcu_read_lock(); + list_for_each_entry(skp, &smack_known_list, list) { + if (sap->attr.mls.lvl != skp->smk_netlabel.attr.mls.lvl) + continue; + /* + * Compare the catsets. Use the netlbl APIs. + */ + if ((sap->flags & NETLBL_SECATTR_MLS_CAT) == 0) { + if ((skp->smk_netlabel.flags & + NETLBL_SECATTR_MLS_CAT) == 0) + found = 1; break; - smack_catset_bit(pcat, smack); + } + for (acat = -1, kcat = -1; acat == kcat; ) { + acat = netlbl_secattr_catmap_walk( + sap->attr.mls.cat, acat + 1); + kcat = netlbl_secattr_catmap_walk( + skp->smk_netlabel.attr.mls.cat, + kcat + 1); + if (acat < 0 || kcat < 0) + break; + } + if (acat == kcat) { + found = 1; + break; + } } - /* - * If it is CIPSO using smack direct mapping - * we are already done. WeeHee. - */ - if (sap->attr.mls.lvl == smack_cipso_direct) { - memcpy(sip, smack, SMK_MAXLEN); - return; + rcu_read_unlock(); + + if (found) + return skp; + + if (ssp != NULL && ssp->smk_in == &smack_known_star) + return &smack_known_web; + return &smack_known_star; + } + if ((sap->flags & NETLBL_SECATTR_SECID) != 0) { + /* + * Looks like a fallback, which gives us a secid. + */ + skp = smack_from_secid(sap->attr.secid); + /* + * This has got to be a bug because it is + * impossible to specify a fallback without + * specifying the label, which will ensure + * it has a secid, and the only way to get a + * secid is from a fallback. + */ + BUG_ON(skp == NULL); + return skp; } /* - * Look it up in the supplied table if it is not a direct mapping. + * Without guidance regarding the smack value + * for the packet fall back on the network + * ambient value. */ - smack_from_cipso(sap->attr.mls.lvl, smack, sip); - return; + return smack_net_ambient; +} + +static int smk_skb_to_addr_ipv6(struct sk_buff *skb, struct sockaddr_in6 *sip) +{ + u8 nexthdr; + int offset; + int proto = -EINVAL; + struct ipv6hdr _ipv6h; + struct ipv6hdr *ip6; + __be16 frag_off; + struct tcphdr _tcph, *th; + struct udphdr _udph, *uh; + struct dccp_hdr _dccph, *dh; + + sip->sin6_port = 0; + + offset = skb_network_offset(skb); + ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h); + if (ip6 == NULL) + return -EINVAL; + sip->sin6_addr = ip6->saddr; + + nexthdr = ip6->nexthdr; + offset += sizeof(_ipv6h); + offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off); + if (offset < 0) + return -EINVAL; + + proto = nexthdr; + switch (proto) { + case IPPROTO_TCP: + th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph); + if (th != NULL) + sip->sin6_port = th->source; + break; + case IPPROTO_UDP: + uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph); + if (uh != NULL) + sip->sin6_port = uh->source; + break; + case IPPROTO_DCCP: + dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph); + if (dh != NULL) + sip->sin6_port = dh->dccph_sport; + break; + } + return proto; } /** @@ -2130,30 +3312,53 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) { struct netlbl_lsm_secattr secattr; struct socket_smack *ssp = sk->sk_security; - char smack[SMK_LABELLEN]; - int rc; + struct smack_known *skp; + struct sockaddr_in6 sadd; + int rc = 0; + struct smk_audit_info ad; +#ifdef CONFIG_AUDIT + struct lsm_network_audit net; +#endif + switch (sk->sk_family) { + case PF_INET: + /* + * Translate what netlabel gave us. + */ + netlbl_secattr_init(&secattr); - if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) - return 0; + rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr); + if (rc == 0) + skp = smack_from_secattr(&secattr, ssp); + else + skp = smack_net_ambient; - /* - * Translate what netlabel gave us. - */ - memset(smack, '\0', SMK_LABELLEN); - netlbl_secattr_init(&secattr); - rc = netlbl_skbuff_getattr(skb, sk->sk_family, &secattr); - if (rc == 0) - smack_from_secattr(&secattr, smack); - else - strncpy(smack, smack_net_ambient, SMK_MAXLEN); - netlbl_secattr_destroy(&secattr); - /* - * Receiving a packet requires that the other end - * be able to write here. Read access is not required. - * This is the simplist possible security model - * for networking. - */ - return smk_access(smack, ssp->smk_in, MAY_WRITE); + netlbl_secattr_destroy(&secattr); + +#ifdef CONFIG_AUDIT + smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); + ad.a.u.net->family = sk->sk_family; + ad.a.u.net->netif = skb->skb_iif; + ipv4_skb_to_auditdata(skb, &ad.a, NULL); +#endif + /* + * Receiving a packet requires that the other end + * be able to write here. Read access is not required. + * This is the simplist possible security model + * for networking. + */ + rc = smk_access(skp, ssp->smk_in->smk_known, MAY_WRITE, &ad); + if (rc != 0) + netlbl_skbuff_err(skb, rc, 0); + break; + case PF_INET6: + rc = smk_skb_to_addr_ipv6(skb, &sadd); + if (rc == IPPROTO_UDP || rc == IPPROTO_TCP) + rc = smk_ipv6_port_check(sk, &sadd, SMK_RECEIVING); + else + rc = 0; + break; + } + return rc; } /** @@ -2161,7 +3366,7 @@ static int smack_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb) * @sock: the socket * @optval: user's destination * @optlen: size thereof - * @len: max thereoe + * @len: max thereof * * returns zero on success, an error code otherwise */ @@ -2170,15 +3375,19 @@ static int smack_socket_getpeersec_stream(struct socket *sock, int __user *optlen, unsigned len) { struct socket_smack *ssp; - int slen; + char *rcp = ""; + int slen = 1; int rc = 0; ssp = sock->sk->sk_security; - slen = strlen(ssp->smk_packet) + 1; + if (ssp->smk_packet != NULL) { + rcp = ssp->smk_packet->smk_known; + slen = strlen(rcp) + 1; + } if (slen > len) rc = -ERANGE; - else if (copy_to_user(optval, ssp->smk_packet, slen) != 0) + else if (copy_to_user(optval, rcp, slen) != 0) rc = -EFAULT; if (put_user(slen, optlen) != 0) @@ -2190,7 +3399,7 @@ static int smack_socket_getpeersec_stream(struct socket *sock, /** * smack_socket_getpeersec_dgram - pull in packet label - * @sock: the socket + * @sock: the peer socket * @skb: packet data * @secid: pointer to where to put the secid of the packet * @@ -2201,72 +3410,65 @@ static int smack_socket_getpeersec_dgram(struct socket *sock, { struct netlbl_lsm_secattr secattr; - struct sock *sk; - char smack[SMK_LABELLEN]; - int family = PF_INET; - u32 s; + struct socket_smack *ssp = NULL; + struct smack_known *skp; + int family = PF_UNSPEC; + u32 s = 0; /* 0 is the invalid secid */ int rc; - /* - * Only works for families with packets. - */ - if (sock != NULL) { - sk = sock->sk; - if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) - return 0; - family = sk->sk_family; + if (skb != NULL) { + if (skb->protocol == htons(ETH_P_IP)) + family = PF_INET; + else if (skb->protocol == htons(ETH_P_IPV6)) + family = PF_INET6; } - /* - * Translate what netlabel gave us. - */ - memset(smack, '\0', SMK_LABELLEN); - netlbl_secattr_init(&secattr); - rc = netlbl_skbuff_getattr(skb, family, &secattr); - if (rc == 0) - smack_from_secattr(&secattr, smack); - netlbl_secattr_destroy(&secattr); + if (family == PF_UNSPEC && sock != NULL) + family = sock->sk->sk_family; - /* - * Give up if we couldn't get anything - */ - if (rc != 0) - return rc; - - s = smack_to_secid(smack); + if (family == PF_UNIX) { + ssp = sock->sk->sk_security; + s = ssp->smk_out->smk_secid; + } else if (family == PF_INET || family == PF_INET6) { + /* + * Translate what netlabel gave us. + */ + if (sock != NULL && sock->sk != NULL) + ssp = sock->sk->sk_security; + netlbl_secattr_init(&secattr); + rc = netlbl_skbuff_getattr(skb, family, &secattr); + if (rc == 0) { + skp = smack_from_secattr(&secattr, ssp); + s = skp->smk_secid; + } + netlbl_secattr_destroy(&secattr); + } + *secid = s; if (s == 0) return -EINVAL; - - *secid = s; return 0; } /** - * smack_sock_graft - graft access state between two sockets - * @sk: fresh sock - * @parent: donor socket + * smack_sock_graft - Initialize a newly created socket with an existing sock + * @sk: child sock + * @parent: parent socket * - * Sets the netlabel socket state on sk from parent + * Set the smk_{in,out} state of an existing sock based on the process that + * is creating the new socket. */ static void smack_sock_graft(struct sock *sk, struct socket *parent) { struct socket_smack *ssp; - int rc; - - if (sk == NULL) - return; + struct smack_known *skp = smk_of_current(); - if (sk->sk_family != PF_INET && sk->sk_family != PF_INET6) + if (sk == NULL || + (sk->sk_family != PF_INET && sk->sk_family != PF_INET6)) return; ssp = sk->sk_security; - ssp->smk_in = current->security; - ssp->smk_out = current->security; - ssp->smk_packet[0] = '\0'; - - rc = smack_netlabel(sk); - if (rc != 0) - printk(KERN_WARNING "Smack: \"%s\" netlbl error %d.\n", - __func__, -rc); + ssp->smk_in = skp; + ssp->smk_out = skp; + /* cssp->smk_packet is already set in smack_inet_csk_clone() */ } /** @@ -2281,36 +3483,98 @@ static void smack_sock_graft(struct sock *sk, struct socket *parent) static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, struct request_sock *req) { - struct netlbl_lsm_secattr skb_secattr; + u16 family = sk->sk_family; + struct smack_known *skp; struct socket_smack *ssp = sk->sk_security; - char smack[SMK_LABELLEN]; + struct netlbl_lsm_secattr secattr; + struct sockaddr_in addr; + struct iphdr *hdr; + char *hsp; int rc; + struct smk_audit_info ad; +#ifdef CONFIG_AUDIT + struct lsm_network_audit net; +#endif - if (skb == NULL) - return -EACCES; + if (family == PF_INET6) { + /* + * Handle mapped IPv4 packets arriving + * via IPv6 sockets. Don't set up netlabel + * processing on IPv6. + */ + if (skb->protocol == htons(ETH_P_IP)) + family = PF_INET; + else + return 0; + } - memset(smack, '\0', SMK_LABELLEN); - netlbl_secattr_init(&skb_secattr); - rc = netlbl_skbuff_getattr(skb, sk->sk_family, &skb_secattr); + netlbl_secattr_init(&secattr); + rc = netlbl_skbuff_getattr(skb, family, &secattr); if (rc == 0) - smack_from_secattr(&skb_secattr, smack); + skp = smack_from_secattr(&secattr, ssp); else - strncpy(smack, smack_known_huh.smk_known, SMK_MAXLEN); - netlbl_secattr_destroy(&skb_secattr); + skp = &smack_known_huh; + netlbl_secattr_destroy(&secattr); + +#ifdef CONFIG_AUDIT + smk_ad_init_net(&ad, __func__, LSM_AUDIT_DATA_NET, &net); + ad.a.u.net->family = family; + ad.a.u.net->netif = skb->skb_iif; + ipv4_skb_to_auditdata(skb, &ad.a, NULL); +#endif /* - * Receiving a packet requires that the other end - * be able to write here. Read access is not required. - * - * If the request is successful save the peer's label - * so that SO_PEERCRED can report it. + * Receiving a packet requires that the other end be able to write + * here. Read access is not required. */ - rc = smk_access(smack, ssp->smk_in, MAY_WRITE); - if (rc == 0) - strncpy(ssp->smk_packet, smack, SMK_MAXLEN); + rc = smk_access(skp, ssp->smk_in->smk_known, MAY_WRITE, &ad); + if (rc != 0) + return rc; + + /* + * Save the peer's label in the request_sock so we can later setup + * smk_packet in the child socket so that SO_PEERCRED can report it. + */ + req->peer_secid = skp->smk_secid; + + /* + * We need to decide if we want to label the incoming connection here + * if we do we only need to label the request_sock and the stack will + * propagate the wire-label to the sock when it is created. + */ + hdr = ip_hdr(skb); + addr.sin_addr.s_addr = hdr->saddr; + rcu_read_lock(); + hsp = smack_host_label(&addr); + rcu_read_unlock(); + + if (hsp == NULL) + rc = netlbl_req_setattr(req, &skp->smk_netlabel); + else + netlbl_req_delattr(req); return rc; } +/** + * smack_inet_csk_clone - Copy the connection information to the new socket + * @sk: the new socket + * @req: the connection's request_sock + * + * Transfer the connection's peer label to the newly created socket. + */ +static void smack_inet_csk_clone(struct sock *sk, + const struct request_sock *req) +{ + struct socket_smack *ssp = sk->sk_security; + struct smack_known *skp; + + if (req->peer_secid != 0) { + skp = smack_from_secid(req->peer_secid); + ssp->smk_packet = skp; + } else + ssp->smk_packet = NULL; +} + /* * Key management security hooks * @@ -2323,17 +3587,19 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb, /** * smack_key_alloc - Set the key security blob * @key: object - * @tsk: the task associated with the key + * @cred: the credentials to use * @flags: unused * * No allocation required * * Returns 0 */ -static int smack_key_alloc(struct key *key, struct task_struct *tsk, +static int smack_key_alloc(struct key *key, const struct cred *cred, unsigned long flags) { - key->security = tsk->security; + struct smack_known *skp = smk_of_task(cred->security); + + key->security = skp->smk_known; return 0; } @@ -2351,16 +3617,19 @@ static void smack_key_free(struct key *key) /* * smack_key_permission - Smack access on a key * @key_ref: gets to the object - * @context: task involved + * @cred: the credentials to use * @perm: unused * * Return 0 if the task has read and write to the object, * an error code otherwise */ static int smack_key_permission(key_ref_t key_ref, - struct task_struct *context, key_perm_t perm) + const struct cred *cred, unsigned perm) { struct key *keyp; + struct smk_audit_info ad; + struct smack_known *tkp = smk_of_task(cred->security); + int request = 0; keyp = key_ref_to_ptr(key_ref); if (keyp == NULL) @@ -2374,14 +3643,149 @@ static int smack_key_permission(key_ref_t key_ref, /* * This should not occur */ - if (context->security == NULL) + if (tkp == NULL) return -EACCES; - - return smk_access(context->security, keyp->security, MAY_READWRITE); +#ifdef CONFIG_AUDIT + smk_ad_init(&ad, __func__, LSM_AUDIT_DATA_KEY); + ad.a.u.key_struct.key = keyp->serial; + ad.a.u.key_struct.key_desc = keyp->description; +#endif + if (perm & KEY_NEED_READ) + request = MAY_READ; + if (perm & (KEY_NEED_WRITE | KEY_NEED_LINK | KEY_NEED_SETATTR)) + request = MAY_WRITE; + return smk_access(tkp, keyp->security, request, &ad); } #endif /* CONFIG_KEYS */ /* + * Smack Audit hooks + * + * Audit requires a unique representation of each Smack specific + * rule. This unique representation is used to distinguish the + * object to be audited from remaining kernel objects and also + * works as a glue between the audit hooks. + * + * Since repository entries are added but never deleted, we'll use + * the smack_known label address related to the given audit rule as + * the needed unique representation. This also better fits the smack + * model where nearly everything is a label. + */ +#ifdef CONFIG_AUDIT + +/** + * smack_audit_rule_init - Initialize a smack audit rule + * @field: audit rule fields given from user-space (audit.h) + * @op: required testing operator (=, !=, >, <, ...) + * @rulestr: smack label to be audited + * @vrule: pointer to save our own audit rule representation + * + * Prepare to audit cases where (@field @op @rulestr) is true. + * The label to be audited is created if necessay. + */ +static int smack_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) +{ + char **rule = (char **)vrule; + *rule = NULL; + + if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) + return -EINVAL; + + if (op != Audit_equal && op != Audit_not_equal) + return -EINVAL; + + *rule = smk_import(rulestr, 0); + + return 0; +} + +/** + * smack_audit_rule_known - Distinguish Smack audit rules + * @krule: rule of interest, in Audit kernel representation format + * + * This is used to filter Smack rules from remaining Audit ones. + * If it's proved that this rule belongs to us, the + * audit_rule_match hook will be called to do the final judgement. + */ +static int smack_audit_rule_known(struct audit_krule *krule) +{ + struct audit_field *f; + int i; + + for (i = 0; i < krule->field_count; i++) { + f = &krule->fields[i]; + + if (f->type == AUDIT_SUBJ_USER || f->type == AUDIT_OBJ_USER) + return 1; + } + + return 0; +} + +/** + * smack_audit_rule_match - Audit given object ? + * @secid: security id for identifying the object to test + * @field: audit rule flags given from user-space + * @op: required testing operator + * @vrule: smack internal rule presentation + * @actx: audit context associated with the check + * + * The core Audit hook. It's used to take the decision of + * whether to audit or not to audit a given object. + */ +static int smack_audit_rule_match(u32 secid, u32 field, u32 op, void *vrule, + struct audit_context *actx) +{ + struct smack_known *skp; + char *rule = vrule; + + if (unlikely(!rule)) { + WARN_ONCE(1, "Smack: missing rule\n"); + return -ENOENT; + } + + if (field != AUDIT_SUBJ_USER && field != AUDIT_OBJ_USER) + return 0; + + skp = smack_from_secid(secid); + + /* + * No need to do string comparisons. If a match occurs, + * both pointers will point to the same smack_known + * label. + */ + if (op == Audit_equal) + return (rule == skp->smk_known); + if (op == Audit_not_equal) + return (rule != skp->smk_known); + + return 0; +} + +/** + * smack_audit_rule_free - free smack rule representation + * @vrule: rule to be freed. + * + * No memory was allocated. + */ +static void smack_audit_rule_free(void *vrule) +{ + /* No-op */ +} + +#endif /* CONFIG_AUDIT */ + +/** + * smack_ismaclabel - check if xattr @name references a smack MAC label + * @name: Full xattr name to check. + */ +static int smack_ismaclabel(const char *name) +{ + return (strcmp(name, XATTR_SMACK_SUFFIX) == 0); +} + + +/** * smack_secid_to_secctx - return the smack label for a secid * @secid: incoming integer * @secdata: destination @@ -2391,14 +3795,15 @@ static int smack_key_permission(key_ref_t key_ref, */ static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { - char *sp = smack_from_secid(secid); + struct smack_known *skp = smack_from_secid(secid); - *secdata = sp; - *seclen = strlen(sp); + if (secdata) + *secdata = skp->smk_known; + *seclen = strlen(skp->smk_known); return 0; } -/* +/** * smack_secctx_to_secid - return the secid for a smack label * @secdata: smack label * @seclen: how long result is @@ -2406,17 +3811,16 @@ static int smack_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) * * Exists for audit and networking code. */ -static int smack_secctx_to_secid(char *secdata, u32 seclen, u32 *secid) +static int smack_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid) { *secid = smack_to_secid(secdata); return 0; } -/* +/** * smack_release_secctx - don't do anything. - * @key_ref: unused - * @context: unused - * @perm: unused + * @secdata: unused + * @seclen: unused * * Exists to make sure nothing gets done, and properly */ @@ -2424,27 +3828,43 @@ static void smack_release_secctx(char *secdata, u32 seclen) { } -static struct security_operations smack_ops = { - .ptrace = smack_ptrace, - .capget = cap_capget, - .capset_check = cap_capset_check, - .capset_set = cap_capset_set, - .capable = cap_capable, - .syslog = smack_syslog, - .settime = cap_settime, - .vm_enough_memory = cap_vm_enough_memory, +static int smack_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen) +{ + return smack_inode_setsecurity(inode, XATTR_SMACK_SUFFIX, ctx, ctxlen, 0); +} + +static int smack_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen) +{ + return __vfs_setxattr_noperm(dentry, XATTR_NAME_SMACK, ctx, ctxlen, 0); +} + +static int smack_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen) +{ + int len = 0; + len = smack_inode_getsecurity(inode, XATTR_SMACK_SUFFIX, ctx, true); - .bprm_apply_creds = cap_bprm_apply_creds, - .bprm_set_security = cap_bprm_set_security, - .bprm_secureexec = cap_bprm_secureexec, + if (len < 0) + return len; + *ctxlen = len; + return 0; +} + +struct security_operations smack_ops = { + .name = "smack", + + .ptrace_access_check = smack_ptrace_access_check, + .ptrace_traceme = smack_ptrace_traceme, + .syslog = smack_syslog, .sb_alloc_security = smack_sb_alloc_security, .sb_free_security = smack_sb_free_security, .sb_copy_data = smack_sb_copy_data, .sb_kern_mount = smack_sb_kern_mount, .sb_statfs = smack_sb_statfs, - .sb_mount = smack_sb_mount, - .sb_umount = smack_sb_umount, + + .bprm_set_creds = smack_bprm_set_creds, + .bprm_committing_creds = smack_bprm_committing_creds, + .bprm_secureexec = smack_bprm_secureexec, .inode_alloc_security = smack_inode_alloc_security, .inode_free_security = smack_inode_free_security, @@ -2460,11 +3880,10 @@ static struct security_operations smack_ops = { .inode_post_setxattr = smack_inode_post_setxattr, .inode_getxattr = smack_inode_getxattr, .inode_removexattr = smack_inode_removexattr, - .inode_need_killpriv = cap_inode_need_killpriv, - .inode_killpriv = cap_inode_killpriv, .inode_getsecurity = smack_inode_getsecurity, .inode_setsecurity = smack_inode_setsecurity, .inode_listsecurity = smack_inode_listsecurity, + .inode_getsecid = smack_inode_getsecid, .file_permission = smack_file_permission, .file_alloc_security = smack_file_alloc_security, @@ -2472,13 +3891,20 @@ static struct security_operations smack_ops = { .file_ioctl = smack_file_ioctl, .file_lock = smack_file_lock, .file_fcntl = smack_file_fcntl, + .mmap_file = smack_mmap_file, + .mmap_addr = cap_mmap_addr, .file_set_fowner = smack_file_set_fowner, .file_send_sigiotask = smack_file_send_sigiotask, .file_receive = smack_file_receive, - .task_alloc_security = smack_task_alloc_security, - .task_free_security = smack_task_free_security, - .task_post_setuid = cap_task_post_setuid, + .file_open = smack_file_open, + + .cred_alloc_blank = smack_cred_alloc_blank, + .cred_free = smack_cred_free, + .cred_prepare = smack_cred_prepare, + .cred_transfer = smack_cred_transfer, + .kernel_act_as = smack_kernel_act_as, + .kernel_create_files_as = smack_kernel_create_files_as, .task_setpgid = smack_task_setpgid, .task_getpgid = smack_task_getpgid, .task_getsid = smack_task_getsid, @@ -2491,10 +3917,10 @@ static struct security_operations smack_ops = { .task_movememory = smack_task_movememory, .task_kill = smack_task_kill, .task_wait = smack_task_wait, - .task_reparent_to_init = cap_task_reparent_to_init, .task_to_inode = smack_task_to_inode, .ipc_permission = smack_ipc_permission, + .ipc_getsecid = smack_ipc_getsecid, .msg_msg_alloc_security = smack_msg_msg_alloc_security, .msg_msg_free_security = smack_msg_msg_free_security, @@ -2518,11 +3944,6 @@ static struct security_operations smack_ops = { .sem_semctl = smack_sem_semctl, .sem_semop = smack_sem_semop, - .netlink_send = cap_netlink_send, - .netlink_recv = cap_netlink_recv, - - .register_security = smack_register_security, - .d_instantiate = smack_d_instantiate, .getprocattr = smack_getprocattr, @@ -2532,6 +3953,9 @@ static struct security_operations smack_ops = { .unix_may_send = smack_unix_may_send, .socket_post_create = smack_socket_post_create, + .socket_bind = smack_socket_bind, + .socket_connect = smack_socket_connect, + .socket_sendmsg = smack_socket_sendmsg, .socket_sock_rcv_skb = smack_socket_sock_rcv_skb, .socket_getpeersec_stream = smack_socket_getpeersec_stream, .socket_getpeersec_dgram = smack_socket_getpeersec_dgram, @@ -2539,17 +3963,64 @@ static struct security_operations smack_ops = { .sk_free_security = smack_sk_free_security, .sock_graft = smack_sock_graft, .inet_conn_request = smack_inet_conn_request, + .inet_csk_clone = smack_inet_csk_clone, + /* key management security hooks */ #ifdef CONFIG_KEYS .key_alloc = smack_key_alloc, .key_free = smack_key_free, .key_permission = smack_key_permission, #endif /* CONFIG_KEYS */ + + /* Audit hooks */ +#ifdef CONFIG_AUDIT + .audit_rule_init = smack_audit_rule_init, + .audit_rule_known = smack_audit_rule_known, + .audit_rule_match = smack_audit_rule_match, + .audit_rule_free = smack_audit_rule_free, +#endif /* CONFIG_AUDIT */ + + .ismaclabel = smack_ismaclabel, .secid_to_secctx = smack_secid_to_secctx, .secctx_to_secid = smack_secctx_to_secid, .release_secctx = smack_release_secctx, + .inode_notifysecctx = smack_inode_notifysecctx, + .inode_setsecctx = smack_inode_setsecctx, + .inode_getsecctx = smack_inode_getsecctx, }; + +static __init void init_smack_known_list(void) +{ + /* + * Initialize rule list locks + */ + mutex_init(&smack_known_huh.smk_rules_lock); + mutex_init(&smack_known_hat.smk_rules_lock); + mutex_init(&smack_known_floor.smk_rules_lock); + mutex_init(&smack_known_star.smk_rules_lock); + mutex_init(&smack_known_invalid.smk_rules_lock); + mutex_init(&smack_known_web.smk_rules_lock); + /* + * Initialize rule lists + */ + INIT_LIST_HEAD(&smack_known_huh.smk_rules); + INIT_LIST_HEAD(&smack_known_hat.smk_rules); + INIT_LIST_HEAD(&smack_known_star.smk_rules); + INIT_LIST_HEAD(&smack_known_floor.smk_rules); + INIT_LIST_HEAD(&smack_known_invalid.smk_rules); + INIT_LIST_HEAD(&smack_known_web.smk_rules); + /* + * Create the known labels list + */ + smk_insert_entry(&smack_known_huh); + smk_insert_entry(&smack_known_hat); + smk_insert_entry(&smack_known_star); + smk_insert_entry(&smack_known_floor); + smk_insert_entry(&smack_known_invalid); + smk_insert_entry(&smack_known_web); +} + /** * smack_init - initialize the smack system * @@ -2557,22 +4028,27 @@ static struct security_operations smack_ops = { */ static __init int smack_init(void) { + struct cred *cred; + struct task_smack *tsp; + + if (!security_module_enable(&smack_ops)) + return 0; + + tsp = new_task_smack(&smack_known_floor, &smack_known_floor, + GFP_KERNEL); + if (tsp == NULL) + return -ENOMEM; + printk(KERN_INFO "Smack: Initializing.\n"); /* * Set the security state for the initial task. */ - current->security = &smack_known_floor.smk_known; + cred = (struct cred *) current->cred; + cred->security = tsp; - /* - * Initialize locks - */ - spin_lock_init(&smack_known_unset.smk_cipsolock); - spin_lock_init(&smack_known_huh.smk_cipsolock); - spin_lock_init(&smack_known_hat.smk_cipsolock); - spin_lock_init(&smack_known_star.smk_cipsolock); - spin_lock_init(&smack_known_floor.smk_cipsolock); - spin_lock_init(&smack_known_invalid.smk_cipsolock); + /* initialize the smack_known_list */ + init_smack_known_list(); /* * Register with LSM @@ -2588,4 +4064,3 @@ static __init int smack_init(void) * all processes and objects when they are created. */ security_initcall(smack_init); - |